Practice 300 Chemical Kinetics and Chemical Thermodynamics MCQs with answers covering thermodynamics laws, enthalpy, entropy, Gibbs free energy, equilibrium, reaction rates, rate laws, Arrhenius equation, and mechanisms.
Chemical Kinetics and Chemical Thermodynamics MCQs with Answers
A complete physical chemistry practice bank covering thermodynamics, thermochemistry, entropy, Gibbs free energy, equilibrium, reaction rates, rate laws and mechanisms.
About This MCQ Bank
This ElecturesAI resource is designed for quick revision and exam practice in Chemical Kinetics and Chemical Thermodynamics. It covers conceptual and calculation-oriented physical chemistry topics without mentioning any university or semester.
Reference Focus
Prepared around common physical chemistry concepts including laws of thermodynamics, heat capacity, calorimetry, Hess’s law, entropy, Gibbs energy, equilibrium, reaction order, Arrhenius equation and mechanisms.
Covered Topics
- Chemical ThermodynamicsSystems, surroundings, state functions, zeroth, first, second and third laws.
- Thermochemistry and CalorimetryEnthalpy, heat capacity, Hess’s law, constant heat summation and calorimetry.
- Entropy and Free EnergyEntropy, spontaneity, Carnot cycle, Gibbs energy, equilibrium, fugacity and activity.
- Chemical KineticsReaction rates, rate laws, reaction order, half-life, Arrhenius equation and mechanisms.
What is meant by thermodynamics in physical chemistry?
- the classification of minerals
- the study of heat, work, energy and their transformations
- the study of reaction colors only
- the naming of organic compounds
Show Answer
Answer: the study of heat, work, energy and their transformations
Thermodynamics explains energy changes in physical and chemical processes.
Which option best explains thermodynamics?
- the study of reaction colors only
- the naming of organic compounds
- the study of heat, work, energy and their transformations
- the classification of minerals
Show Answer
Answer: the study of heat, work, energy and their transformations
The correct concept is: the study of heat, work, energy and their transformations. Thermodynamics explains energy changes in physical and chemical processes.
A correct statement about thermodynamics is:
- the study of heat, work, energy and their transformations
- the classification of minerals
- the study of reaction colors only
- the naming of organic compounds
Show Answer
Answer: the study of heat, work, energy and their transformations
Thermodynamics is important because thermodynamics explains energy changes in physical and chemical processes.
What is meant by system in physical chemistry?
- the part of the universe selected for thermodynamic study
- a random table of data
- everything outside the boundary
- only the measuring instrument
Show Answer
Answer: the part of the universe selected for thermodynamic study
A system may be a gas, solution, reaction mixture or any defined matter under observation.
Which option best explains system?
- a random table of data
- everything outside the boundary
- only the measuring instrument
- the part of the universe selected for thermodynamic study
Show Answer
Answer: the part of the universe selected for thermodynamic study
The correct concept is: the part of the universe selected for thermodynamic study. A system may be a gas, solution, reaction mixture or any defined matter under observation.
A correct statement about system is:
- a random table of data
- everything outside the boundary
- the part of the universe selected for thermodynamic study
- only the measuring instrument
Show Answer
Answer: the part of the universe selected for thermodynamic study
System is important because a system may be a gas, solution, reaction mixture or any defined matter under observation.
What is meant by surroundings in physical chemistry?
- the internal energy of a sample
- only the reacting substance
- the molecular formula of a compound
- everything outside the thermodynamic system
Show Answer
Answer: everything outside the thermodynamic system
The surroundings exchange heat, work or matter with the system depending on the boundary.
Which option best explains surroundings?
- the molecular formula of a compound
- only the reacting substance
- the internal energy of a sample
- everything outside the thermodynamic system
Show Answer
Answer: everything outside the thermodynamic system
The correct concept is: everything outside the thermodynamic system. The surroundings exchange heat, work or matter with the system depending on the boundary.
A correct statement about surroundings is:
- the internal energy of a sample
- only the reacting substance
- everything outside the thermodynamic system
- the molecular formula of a compound
Show Answer
Answer: everything outside the thermodynamic system
Surroundings is important because the surroundings exchange heat, work or matter with the system depending on the boundary.
What is meant by boundary in physical chemistry?
- the final product of a reaction
- the real or imaginary surface separating system from surroundings
- a catalyst used in a mechanism
- the boiling point of a liquid
Show Answer
Answer: the real or imaginary surface separating system from surroundings
Boundaries define what is included in the thermodynamic system.
Which option best explains boundary?
- a catalyst used in a mechanism
- the real or imaginary surface separating system from surroundings
- the final product of a reaction
- the boiling point of a liquid
Show Answer
Answer: the real or imaginary surface separating system from surroundings
The correct concept is: the real or imaginary surface separating system from surroundings. Boundaries define what is included in the thermodynamic system.
A correct statement about boundary is:
- the final product of a reaction
- the real or imaginary surface separating system from surroundings
- a catalyst used in a mechanism
- the boiling point of a liquid
Show Answer
Answer: the real or imaginary surface separating system from surroundings
Boundary is important because boundaries define what is included in the thermodynamic system.
What is meant by open system in physical chemistry?
- a system with no boundary
- a system exchanging only work but no matter
- a system exchanging neither heat nor matter
- a system that can exchange both matter and energy with surroundings
Show Answer
Answer: a system that can exchange both matter and energy with surroundings
An open beaker can exchange vapor, heat and sometimes material with the environment.
Which option best explains open system?
- a system with no boundary
- a system exchanging only work but no matter
- a system exchanging neither heat nor matter
- a system that can exchange both matter and energy with surroundings
Show Answer
Answer: a system that can exchange both matter and energy with surroundings
The correct concept is: a system that can exchange both matter and energy with surroundings. An open beaker can exchange vapor, heat and sometimes material with the environment.
A correct statement about open system is:
- a system with no boundary
- a system exchanging only work but no matter
- a system exchanging neither heat nor matter
- a system that can exchange both matter and energy with surroundings
Show Answer
Answer: a system that can exchange both matter and energy with surroundings
Open system is important because an open beaker can exchange vapor, heat and sometimes material with the environment.
What is meant by closed system in physical chemistry?
- a system that exchanges matter freely
- a system without energy change
- a system that exchanges energy but not matter with surroundings
- a system made only of solids
Show Answer
Answer: a system that exchanges energy but not matter with surroundings
A sealed container can be heated or cooled without losing material.
Which option best explains closed system?
- a system without energy change
- a system made only of solids
- a system that exchanges energy but not matter with surroundings
- a system that exchanges matter freely
Show Answer
Answer: a system that exchanges energy but not matter with surroundings
The correct concept is: a system that exchanges energy but not matter with surroundings. A sealed container can be heated or cooled without losing material.
A correct statement about closed system is:
- a system made only of solids
- a system without energy change
- a system that exchanges matter freely
- a system that exchanges energy but not matter with surroundings
Show Answer
Answer: a system that exchanges energy but not matter with surroundings
Closed system is important because a sealed container can be heated or cooled without losing material.
What is meant by isolated system in physical chemistry?
- a system with no thermodynamic properties
- a system that exchanges neither matter nor energy with surroundings
- a system exchanging matter only
- a system exchanging heat quickly
Show Answer
Answer: a system that exchanges neither matter nor energy with surroundings
An ideal thermos is often used as an approximate example of an isolated system.
Which option best explains isolated system?
- a system that exchanges neither matter nor energy with surroundings
- a system exchanging heat quickly
- a system exchanging matter only
- a system with no thermodynamic properties
Show Answer
Answer: a system that exchanges neither matter nor energy with surroundings
The correct concept is: a system that exchanges neither matter nor energy with surroundings. An ideal thermos is often used as an approximate example of an isolated system.
A correct statement about isolated system is:
- a system exchanging matter only
- a system that exchanges neither matter nor energy with surroundings
- a system exchanging heat quickly
- a system with no thermodynamic properties
Show Answer
Answer: a system that exchanges neither matter nor energy with surroundings
Isolated system is important because an ideal thermos is often used as an approximate example of an isolated system.
What is meant by state function in physical chemistry?
- a value used only in kinetics
- a property that cannot be measured indirectly
- a property depending on the exact route followed
- a property depending only on the current state, not the path
Show Answer
Answer: a property depending only on the current state, not the path
Internal energy, enthalpy, entropy and Gibbs free energy are state functions.
Which option best explains state function?
- a property depending only on the current state, not the path
- a property depending on the exact route followed
- a value used only in kinetics
- a property that cannot be measured indirectly
Show Answer
Answer: a property depending only on the current state, not the path
The correct concept is: a property depending only on the current state, not the path. Internal energy, enthalpy, entropy and Gibbs free energy are state functions.
A correct statement about state function is:
- a property depending only on the current state, not the path
- a value used only in kinetics
- a property that cannot be measured indirectly
- a property depending on the exact route followed
Show Answer
Answer: a property depending only on the current state, not the path
State function is important because internal energy, enthalpy, entropy and Gibbs free energy are state functions.
What is meant by path function in physical chemistry?
- a property depending only on initial and final states
- a universal constant for every reaction
- a fixed molecular mass
- a quantity whose value depends on the process path
Show Answer
Answer: a quantity whose value depends on the process path
Heat and work are path functions because their values depend on how the change occurs.
Which option best explains path function?
- a property depending only on initial and final states
- a fixed molecular mass
- a quantity whose value depends on the process path
- a universal constant for every reaction
Show Answer
Answer: a quantity whose value depends on the process path
The correct concept is: a quantity whose value depends on the process path. Heat and work are path functions because their values depend on how the change occurs.
A correct statement about path function is:
- a quantity whose value depends on the process path
- a fixed molecular mass
- a universal constant for every reaction
- a property depending only on initial and final states
Show Answer
Answer: a quantity whose value depends on the process path
Path function is important because heat and work are path functions because their values depend on how the change occurs.
What is meant by thermodynamic equilibrium in physical chemistry?
- a condition of maximum reaction speed
- a condition with no net tendency for macroscopic change
- a state with no molecules present
- a condition where temperature must be zero
Show Answer
Answer: a condition with no net tendency for macroscopic change
At equilibrium, thermal, mechanical and chemical tendencies are balanced.
Which option best explains thermodynamic equilibrium?
- a condition with no net tendency for macroscopic change
- a condition of maximum reaction speed
- a state with no molecules present
- a condition where temperature must be zero
Show Answer
Answer: a condition with no net tendency for macroscopic change
The correct concept is: a condition with no net tendency for macroscopic change. At equilibrium, thermal, mechanical and chemical tendencies are balanced.
A correct statement about thermodynamic equilibrium is:
- a condition of maximum reaction speed
- a state with no molecules present
- a condition with no net tendency for macroscopic change
- a condition where temperature must be zero
Show Answer
Answer: a condition with no net tendency for macroscopic change
Thermodynamic equilibrium is important because at equilibrium, thermal, mechanical and chemical tendencies are balanced.
What is meant by zeroth law of thermodynamics in physical chemistry?
- if two systems are in thermal equilibrium with a third, they are in thermal equilibrium with each other
- entropy of a perfect crystal is zero at absolute zero
- reaction rate doubles for every catalyst
- energy cannot be created or destroyed
Show Answer
Answer: if two systems are in thermal equilibrium with a third, they are in thermal equilibrium with each other
The zeroth law provides the basis for temperature measurement.
Which option best explains zeroth law of thermodynamics?
- entropy of a perfect crystal is zero at absolute zero
- energy cannot be created or destroyed
- reaction rate doubles for every catalyst
- if two systems are in thermal equilibrium with a third, they are in thermal equilibrium with each other
Show Answer
Answer: if two systems are in thermal equilibrium with a third, they are in thermal equilibrium with each other
The correct concept is: if two systems are in thermal equilibrium with a third, they are in thermal equilibrium with each other. The zeroth law provides the basis for temperature measurement.
A correct statement about zeroth law of thermodynamics is:
- energy cannot be created or destroyed
- entropy of a perfect crystal is zero at absolute zero
- if two systems are in thermal equilibrium with a third, they are in thermal equilibrium with each other
- reaction rate doubles for every catalyst
Show Answer
Answer: if two systems are in thermal equilibrium with a third, they are in thermal equilibrium with each other
Zeroth law of thermodynamics is important because the zeroth law provides the basis for temperature measurement.
What is meant by temperature in physical chemistry?
- the molecular weight of a substance
- a measure related to the direction of heat flow
- the total heat content of a body
- the volume of a sample only
Show Answer
Answer: a measure related to the direction of heat flow
Heat flows spontaneously from higher temperature to lower temperature objects.
Which option best explains temperature?
- the volume of a sample only
- the total heat content of a body
- the molecular weight of a substance
- a measure related to the direction of heat flow
Show Answer
Answer: a measure related to the direction of heat flow
The correct concept is: a measure related to the direction of heat flow. Heat flows spontaneously from higher temperature to lower temperature objects.
A correct statement about temperature is:
- the total heat content of a body
- the molecular weight of a substance
- a measure related to the direction of heat flow
- the volume of a sample only
Show Answer
Answer: a measure related to the direction of heat flow
Temperature is important because heat flows spontaneously from higher temperature to lower temperature objects.
What is meant by first law of thermodynamics in physical chemistry?
- energy is conserved during thermodynamic processes
- entropy of the universe always decreases
- pressure is always constant in reactions
- all reactions must be first order
Show Answer
Answer: energy is conserved during thermodynamic processes
The first law relates changes in internal energy to heat and work.
Which option best explains first law of thermodynamics?
- all reactions must be first order
- energy is conserved during thermodynamic processes
- pressure is always constant in reactions
- entropy of the universe always decreases
Show Answer
Answer: energy is conserved during thermodynamic processes
The correct concept is: energy is conserved during thermodynamic processes. The first law relates changes in internal energy to heat and work.
A correct statement about first law of thermodynamics is:
- pressure is always constant in reactions
- energy is conserved during thermodynamic processes
- entropy of the universe always decreases
- all reactions must be first order
Show Answer
Answer: energy is conserved during thermodynamic processes
First law of thermodynamics is important because the first law relates changes in internal energy to heat and work.
What is meant by mathematical form of first law in physical chemistry?
- k = Ae^(Ea/RT)
- ΔG = ΔH + TΔS
- pH = -log[OH⁻]
- ΔU = q + w
Show Answer
Answer: ΔU = q + w
This convention treats heat added to the system and work done on the system as positive.
Which option best explains mathematical form of first law?
- pH = -log[OH⁻]
- ΔG = ΔH + TΔS
- k = Ae^(Ea/RT)
- ΔU = q + w
Show Answer
Answer: ΔU = q + w
The correct concept is: ΔU = q + w. This convention treats heat added to the system and work done on the system as positive.
A correct statement about mathematical form of first law is:
- ΔG = ΔH + TΔS
- pH = -log[OH⁻]
- k = Ae^(Ea/RT)
- ΔU = q + w
Show Answer
Answer: ΔU = q + w
Mathematical form of first law is important because this convention treats heat added to the system and work done on the system as positive.
What is meant by second law of thermodynamics in physical chemistry?
- energy is destroyed in every reaction
- the entropy of the universe increases for spontaneous processes
- all collisions lead to reaction
- heat capacity is always zero
Show Answer
Answer: the entropy of the universe increases for spontaneous processes
The second law provides a criterion for natural direction of change.
Which option best explains second law of thermodynamics?
- heat capacity is always zero
- the entropy of the universe increases for spontaneous processes
- all collisions lead to reaction
- energy is destroyed in every reaction
Show Answer
Answer: the entropy of the universe increases for spontaneous processes
The correct concept is: the entropy of the universe increases for spontaneous processes. The second law provides a criterion for natural direction of change.
A correct statement about second law of thermodynamics is:
- heat capacity is always zero
- all collisions lead to reaction
- energy is destroyed in every reaction
- the entropy of the universe increases for spontaneous processes
Show Answer
Answer: the entropy of the universe increases for spontaneous processes
Second law of thermodynamics is important because the second law provides a criterion for natural direction of change.
What is meant by third law of thermodynamics in physical chemistry?
- all reactions are reversible
- the entropy of a perfect crystal approaches zero at absolute zero
- every gas is ideal at high pressure
- enthalpy is always equal to pressure
Show Answer
Answer: the entropy of a perfect crystal approaches zero at absolute zero
The third law helps assign absolute entropy values to substances.
Which option best explains third law of thermodynamics?
- enthalpy is always equal to pressure
- every gas is ideal at high pressure
- all reactions are reversible
- the entropy of a perfect crystal approaches zero at absolute zero
Show Answer
Answer: the entropy of a perfect crystal approaches zero at absolute zero
The correct concept is: the entropy of a perfect crystal approaches zero at absolute zero. The third law helps assign absolute entropy values to substances.
A correct statement about third law of thermodynamics is:
- all reactions are reversible
- the entropy of a perfect crystal approaches zero at absolute zero
- enthalpy is always equal to pressure
- every gas is ideal at high pressure
Show Answer
Answer: the entropy of a perfect crystal approaches zero at absolute zero
Third law of thermodynamics is important because the third law helps assign absolute entropy values to substances.
What is meant by thermal equilibrium in physical chemistry?
- a state where all reactions stop permanently
- a condition of maximum pressure only
- a condition in which no net heat flows between bodies in contact
- a state where matter is exchanged rapidly
Show Answer
Answer: a condition in which no net heat flows between bodies in contact
Thermal equilibrium means bodies have the same temperature.
Which option best explains thermal equilibrium?
- a state where matter is exchanged rapidly
- a condition of maximum pressure only
- a condition in which no net heat flows between bodies in contact
- a state where all reactions stop permanently
Show Answer
Answer: a condition in which no net heat flows between bodies in contact
The correct concept is: a condition in which no net heat flows between bodies in contact. Thermal equilibrium means bodies have the same temperature.
A correct statement about thermal equilibrium is:
- a state where all reactions stop permanently
- a condition in which no net heat flows between bodies in contact
- a condition of maximum pressure only
- a state where matter is exchanged rapidly
Show Answer
Answer: a condition in which no net heat flows between bodies in contact
Thermal equilibrium is important because thermal equilibrium means bodies have the same temperature.
What is meant by mechanical equilibrium in physical chemistry?
- zero internal energy
- equal chemical potentials only
- same molecular formula only
- a condition where there is no unbalanced pressure difference
Show Answer
Answer: a condition where there is no unbalanced pressure difference
Mechanical equilibrium means no net macroscopic expansion or compression tendency exists.
Which option best explains mechanical equilibrium?
- same molecular formula only
- equal chemical potentials only
- a condition where there is no unbalanced pressure difference
- zero internal energy
Show Answer
Answer: a condition where there is no unbalanced pressure difference
The correct concept is: a condition where there is no unbalanced pressure difference. Mechanical equilibrium means no net macroscopic expansion or compression tendency exists.
A correct statement about mechanical equilibrium is:
- equal chemical potentials only
- same molecular formula only
- zero internal energy
- a condition where there is no unbalanced pressure difference
Show Answer
Answer: a condition where there is no unbalanced pressure difference
Mechanical equilibrium is important because mechanical equilibrium means no net macroscopic expansion or compression tendency exists.
What is meant by chemical equilibrium in physical chemistry?
- a state where forward and reverse reaction rates are equal
- a state where no molecules collide
- a state where only products exist
- a state that requires zero temperature
Show Answer
Answer: a state where forward and reverse reaction rates are equal
At chemical equilibrium, composition remains constant although dynamic molecular processes continue.
Which option best explains chemical equilibrium?
- a state where forward and reverse reaction rates are equal
- a state where only products exist
- a state that requires zero temperature
- a state where no molecules collide
Show Answer
Answer: a state where forward and reverse reaction rates are equal
The correct concept is: a state where forward and reverse reaction rates are equal. At chemical equilibrium, composition remains constant although dynamic molecular processes continue.
A correct statement about chemical equilibrium is:
- a state where forward and reverse reaction rates are equal
- a state that requires zero temperature
- a state where no molecules collide
- a state where only products exist
Show Answer
Answer: a state where forward and reverse reaction rates are equal
Chemical equilibrium is important because at chemical equilibrium, composition remains constant although dynamic molecular processes continue.
What is meant by spontaneous process in physical chemistry?
- a process that has no entropy change ever
- a process that violates conservation of energy
- a process that must always be extremely fast
- a process that can occur without continuous external driving
Show Answer
Answer: a process that can occur without continuous external driving
Spontaneity is judged by thermodynamic tendency, not necessarily by speed.
Which option best explains spontaneous process?
- a process that must always be extremely fast
- a process that can occur without continuous external driving
- a process that has no entropy change ever
- a process that violates conservation of energy
Show Answer
Answer: a process that can occur without continuous external driving
The correct concept is: a process that can occur without continuous external driving. Spontaneity is judged by thermodynamic tendency, not necessarily by speed.
A correct statement about spontaneous process is:
- a process that must always be extremely fast
- a process that violates conservation of energy
- a process that can occur without continuous external driving
- a process that has no entropy change ever
Show Answer
Answer: a process that can occur without continuous external driving
Spontaneous process is important because spontaneity is judged by thermodynamic tendency, not necessarily by speed.
What is meant by internal energy in physical chemistry?
- only the volume of a gas
- the speed of the reaction only
- the total microscopic energy stored within a system
- only the heat lost to surroundings
Show Answer
Answer: the total microscopic energy stored within a system
Internal energy includes molecular kinetic and potential contributions.
Which option best explains internal energy?
- the total microscopic energy stored within a system
- only the volume of a gas
- only the heat lost to surroundings
- the speed of the reaction only
Show Answer
Answer: the total microscopic energy stored within a system
The correct concept is: the total microscopic energy stored within a system. Internal energy includes molecular kinetic and potential contributions.
A correct statement about internal energy is:
- only the heat lost to surroundings
- the speed of the reaction only
- the total microscopic energy stored within a system
- only the volume of a gas
Show Answer
Answer: the total microscopic energy stored within a system
Internal energy is important because internal energy includes molecular kinetic and potential contributions.
What is meant by heat in physical chemistry?
- energy transferred only by stirring at equal temperature
- the mass of a substance
- energy transferred because of temperature difference
- a fixed state function
Show Answer
Answer: energy transferred because of temperature difference
Heat is not stored as a state property; it is energy in transit.
Which option best explains heat?
- energy transferred only by stirring at equal temperature
- the mass of a substance
- a fixed state function
- energy transferred because of temperature difference
Show Answer
Answer: energy transferred because of temperature difference
The correct concept is: energy transferred because of temperature difference. Heat is not stored as a state property; it is energy in transit.
A correct statement about heat is:
- the mass of a substance
- a fixed state function
- energy transferred only by stirring at equal temperature
- energy transferred because of temperature difference
Show Answer
Answer: energy transferred because of temperature difference
Heat is important because heat is not stored as a state property; it is energy in transit.
What is meant by work in physical chemistry?
- a constant equal to molecular mass
- energy transfer only by temperature difference
- a measure of color intensity
- energy transferred when a force acts through a distance or expansion occurs
Show Answer
Answer: energy transferred when a force acts through a distance or expansion occurs
Pressure-volume work is common when gases expand or contract.
Which option best explains work?
- a measure of color intensity
- a constant equal to molecular mass
- energy transfer only by temperature difference
- energy transferred when a force acts through a distance or expansion occurs
Show Answer
Answer: energy transferred when a force acts through a distance or expansion occurs
The correct concept is: energy transferred when a force acts through a distance or expansion occurs. Pressure-volume work is common when gases expand or contract.
A correct statement about work is:
- a constant equal to molecular mass
- energy transferred when a force acts through a distance or expansion occurs
- energy transfer only by temperature difference
- a measure of color intensity
Show Answer
Answer: energy transferred when a force acts through a distance or expansion occurs
Work is important because pressure-volume work is common when gases expand or contract.
What is meant by pressure-volume work in physical chemistry?
- work associated with expansion or compression against pressure
- work caused only by a change in color
- work equal to entropy times temperature
- work present only in solids
Show Answer
Answer: work associated with expansion or compression against pressure
For constant external pressure, expansion work is often written as w = -PextΔV.
Which option best explains pressure-volume work?
- work equal to entropy times temperature
- work present only in solids
- work associated with expansion or compression against pressure
- work caused only by a change in color
Show Answer
Answer: work associated with expansion or compression against pressure
The correct concept is: work associated with expansion or compression against pressure. For constant external pressure, expansion work is often written as w = -PextΔV.
A correct statement about pressure-volume work is:
- work present only in solids
- work associated with expansion or compression against pressure
- work caused only by a change in color
- work equal to entropy times temperature
Show Answer
Answer: work associated with expansion or compression against pressure
Pressure-volume work is important because for constant external pressure, expansion work is often written as w = -PextΔV.
What is meant by exothermic process in physical chemistry?
- a process that absorbs heat only
- a process that releases heat to the surroundings
- a process with no heat interaction
- a process where pressure must be zero
Show Answer
Answer: a process that releases heat to the surroundings
For many constant-pressure exothermic processes, enthalpy change is negative.
Which option best explains exothermic process?
- a process that releases heat to the surroundings
- a process that absorbs heat only
- a process where pressure must be zero
- a process with no heat interaction
Show Answer
Answer: a process that releases heat to the surroundings
The correct concept is: a process that releases heat to the surroundings. For many constant-pressure exothermic processes, enthalpy change is negative.
A correct statement about exothermic process is:
- a process that releases heat to the surroundings
- a process with no heat interaction
- a process where pressure must be zero
- a process that absorbs heat only
Show Answer
Answer: a process that releases heat to the surroundings
Exothermic process is important because for many constant-pressure exothermic processes, enthalpy change is negative.
What is meant by endothermic process in physical chemistry?
- a reaction with no energy change
- a process that absorbs heat from the surroundings
- a reaction forbidden by kinetics only
- a process that releases heat only
Show Answer
Answer: a process that absorbs heat from the surroundings
Endothermic changes require heat input under the stated conditions.
Which option best explains endothermic process?
- a reaction forbidden by kinetics only
- a reaction with no energy change
- a process that absorbs heat from the surroundings
- a process that releases heat only
Show Answer
Answer: a process that absorbs heat from the surroundings
The correct concept is: a process that absorbs heat from the surroundings. Endothermic changes require heat input under the stated conditions.
A correct statement about endothermic process is:
- a process that absorbs heat from the surroundings
- a reaction forbidden by kinetics only
- a reaction with no energy change
- a process that releases heat only
Show Answer
Answer: a process that absorbs heat from the surroundings
Endothermic process is important because endothermic changes require heat input under the stated conditions.
What is meant by isothermal process in physical chemistry?
- a process that occurs at constant temperature
- a process at constant pressure only
- a process with no molecules
- a process at constant entropy only
Show Answer
Answer: a process that occurs at constant temperature
In an ideal gas isothermal process, internal energy remains constant because temperature is constant.
Which option best explains isothermal process?
- a process at constant pressure only
- a process with no molecules
- a process at constant entropy only
- a process that occurs at constant temperature
Show Answer
Answer: a process that occurs at constant temperature
The correct concept is: a process that occurs at constant temperature. In an ideal gas isothermal process, internal energy remains constant because temperature is constant.
A correct statement about isothermal process is:
- a process at constant entropy only
- a process with no molecules
- a process that occurs at constant temperature
- a process at constant pressure only
Show Answer
Answer: a process that occurs at constant temperature
Isothermal process is important because in an ideal gas isothermal process, internal energy remains constant because temperature is constant.
What is meant by adiabatic process in physical chemistry?
- a process in which no heat is exchanged with surroundings
- a reaction that must be first order
- a process where volume never changes
- a process with unlimited heat transfer
Show Answer
Answer: a process in which no heat is exchanged with surroundings
Adiabatic processes may still involve work and temperature change.
Which option best explains adiabatic process?
- a reaction that must be first order
- a process with unlimited heat transfer
- a process in which no heat is exchanged with surroundings
- a process where volume never changes
Show Answer
Answer: a process in which no heat is exchanged with surroundings
The correct concept is: a process in which no heat is exchanged with surroundings. Adiabatic processes may still involve work and temperature change.
A correct statement about adiabatic process is:
- a reaction that must be first order
- a process with unlimited heat transfer
- a process where volume never changes
- a process in which no heat is exchanged with surroundings
Show Answer
Answer: a process in which no heat is exchanged with surroundings
Adiabatic process is important because adiabatic processes may still involve work and temperature change.
What is meant by isobaric process in physical chemistry?
- a process carried out at constant pressure
- a process at constant entropy only
- a process with no energy terms
- a process at constant volume
Show Answer
Answer: a process carried out at constant pressure
Many laboratory reactions in open vessels are approximately isobaric.
Which option best explains isobaric process?
- a process at constant volume
- a process carried out at constant pressure
- a process at constant entropy only
- a process with no energy terms
Show Answer
Answer: a process carried out at constant pressure
The correct concept is: a process carried out at constant pressure. Many laboratory reactions in open vessels are approximately isobaric.
A correct statement about isobaric process is:
- a process carried out at constant pressure
- a process at constant entropy only
- a process at constant volume
- a process with no energy terms
Show Answer
Answer: a process carried out at constant pressure
Isobaric process is important because many laboratory reactions in open vessels are approximately isobaric.
What is meant by isochoric process in physical chemistry?
- a process carried out at constant volume
- a process where matter must leave the system
- a process at constant pressure only
- a process defined only by concentration
Show Answer
Answer: a process carried out at constant volume
At constant volume, pressure-volume work is zero when volume does not change.
Which option best explains isochoric process?
- a process defined only by concentration
- a process where matter must leave the system
- a process at constant pressure only
- a process carried out at constant volume
Show Answer
Answer: a process carried out at constant volume
The correct concept is: a process carried out at constant volume. At constant volume, pressure-volume work is zero when volume does not change.
A correct statement about isochoric process is:
- a process at constant pressure only
- a process defined only by concentration
- a process where matter must leave the system
- a process carried out at constant volume
Show Answer
Answer: a process carried out at constant volume
Isochoric process is important because at constant volume, pressure-volume work is zero when volume does not change.
What is meant by enthalpy in physical chemistry?
- a path function equal to reaction time
- a catalyst concentration
- a state function defined as H = U + PV
- the number of moles only
Show Answer
Answer: a state function defined as H = U + PV
At constant pressure, enthalpy change equals heat transferred for many processes.
Which option best explains enthalpy?
- a state function defined as H = U + PV
- the number of moles only
- a catalyst concentration
- a path function equal to reaction time
Show Answer
Answer: a state function defined as H = U + PV
The correct concept is: a state function defined as H = U + PV. At constant pressure, enthalpy change equals heat transferred for many processes.
A correct statement about enthalpy is:
- the number of moles only
- a path function equal to reaction time
- a catalyst concentration
- a state function defined as H = U + PV
Show Answer
Answer: a state function defined as H = U + PV
Enthalpy is important because at constant pressure, enthalpy change equals heat transferred for many processes.
What is meant by enthalpy change in physical chemistry?
- the number of collision events only
- the value of activation entropy only
- the change in reaction order
- the heat effect of a process at constant pressure
Show Answer
Answer: the heat effect of a process at constant pressure
For constant-pressure reactions, ΔH is commonly measured as the heat absorbed or released.
Which option best explains enthalpy change?
- the number of collision events only
- the value of activation entropy only
- the change in reaction order
- the heat effect of a process at constant pressure
Show Answer
Answer: the heat effect of a process at constant pressure
The correct concept is: the heat effect of a process at constant pressure. For constant-pressure reactions, ΔH is commonly measured as the heat absorbed or released.
A correct statement about enthalpy change is:
- the number of collision events only
- the change in reaction order
- the heat effect of a process at constant pressure
- the value of activation entropy only
Show Answer
Answer: the heat effect of a process at constant pressure
Enthalpy change is important because for constant-pressure reactions, ΔH is commonly measured as the heat absorbed or released.
What is meant by heat capacity in physical chemistry?
- the heat released at absolute zero only
- the rate constant of a reaction
- the heat required to raise temperature by one degree
- the mass of solvent in grams
Show Answer
Answer: the heat required to raise temperature by one degree
Heat capacity describes how much heat a substance or system can absorb for a temperature rise.
Which option best explains heat capacity?
- the heat released at absolute zero only
- the rate constant of a reaction
- the mass of solvent in grams
- the heat required to raise temperature by one degree
Show Answer
Answer: the heat required to raise temperature by one degree
The correct concept is: the heat required to raise temperature by one degree. Heat capacity describes how much heat a substance or system can absorb for a temperature rise.
A correct statement about heat capacity is:
- the heat required to raise temperature by one degree
- the rate constant of a reaction
- the heat released at absolute zero only
- the mass of solvent in grams
Show Answer
Answer: the heat required to raise temperature by one degree
Heat capacity is important because heat capacity describes how much heat a substance or system can absorb for a temperature rise.
What is meant by specific heat capacity in physical chemistry?
- heat required to raise all samples by ten degrees
- heat required to raise one gram of substance by one degree
- the total heat of combustion only
- a quantity without units
Show Answer
Answer: heat required to raise one gram of substance by one degree
Specific heat capacity is an intensive property commonly used in calorimetry calculations.
Which option best explains specific heat capacity?
- heat required to raise all samples by ten degrees
- heat required to raise one gram of substance by one degree
- a quantity without units
- the total heat of combustion only
Show Answer
Answer: heat required to raise one gram of substance by one degree
The correct concept is: heat required to raise one gram of substance by one degree. Specific heat capacity is an intensive property commonly used in calorimetry calculations.
A correct statement about specific heat capacity is:
- heat required to raise one gram of substance by one degree
- a quantity without units
- heat required to raise all samples by ten degrees
- the total heat of combustion only
Show Answer
Answer: heat required to raise one gram of substance by one degree
Specific heat capacity is important because specific heat capacity is an intensive property commonly used in calorimetry calculations.
What is meant by molar heat capacity in physical chemistry?
- concentration of a catalyst
- heat required to raise one mole of substance by one degree
- reaction rate per mole
- heat required for one molecule to ionize
Show Answer
Answer: heat required to raise one mole of substance by one degree
Molar heat capacity compares thermal response on a per-mole basis.
Which option best explains molar heat capacity?
- concentration of a catalyst
- reaction rate per mole
- heat required for one molecule to ionize
- heat required to raise one mole of substance by one degree
Show Answer
Answer: heat required to raise one mole of substance by one degree
The correct concept is: heat required to raise one mole of substance by one degree. Molar heat capacity compares thermal response on a per-mole basis.
A correct statement about molar heat capacity is:
- reaction rate per mole
- heat required for one molecule to ionize
- concentration of a catalyst
- heat required to raise one mole of substance by one degree
Show Answer
Answer: heat required to raise one mole of substance by one degree
Molar heat capacity is important because molar heat capacity compares thermal response on a per-mole basis.
What is meant by constant-volume heat capacity in physical chemistry?
- heat capacity measured while pressure changes freely
- heat capacity measured while volume remains constant
- the same as equilibrium constant
- heat capacity used only for liquids
Show Answer
Answer: heat capacity measured while volume remains constant
For an ideal gas, Cv relates to internal energy change with temperature.
Which option best explains constant-volume heat capacity?
- heat capacity measured while pressure changes freely
- the same as equilibrium constant
- heat capacity used only for liquids
- heat capacity measured while volume remains constant
Show Answer
Answer: heat capacity measured while volume remains constant
The correct concept is: heat capacity measured while volume remains constant. For an ideal gas, Cv relates to internal energy change with temperature.
A correct statement about constant-volume heat capacity is:
- heat capacity used only for liquids
- heat capacity measured while pressure changes freely
- heat capacity measured while volume remains constant
- the same as equilibrium constant
Show Answer
Answer: heat capacity measured while volume remains constant
Constant-volume heat capacity is important because for an ideal gas, Cv relates to internal energy change with temperature.
What is meant by constant-pressure heat capacity in physical chemistry?
- heat capacity at zero temperature only
- a measure of reaction molecularity
- a property unrelated to temperature
- heat capacity measured while pressure remains constant
Show Answer
Answer: heat capacity measured while pressure remains constant
For an ideal gas, Cp is usually larger than Cv because expansion work is included.
Which option best explains constant-pressure heat capacity?
- a property unrelated to temperature
- heat capacity measured while pressure remains constant
- heat capacity at zero temperature only
- a measure of reaction molecularity
Show Answer
Answer: heat capacity measured while pressure remains constant
The correct concept is: heat capacity measured while pressure remains constant. For an ideal gas, Cp is usually larger than Cv because expansion work is included.
A correct statement about constant-pressure heat capacity is:
- a measure of reaction molecularity
- heat capacity measured while pressure remains constant
- a property unrelated to temperature
- heat capacity at zero temperature only
Show Answer
Answer: heat capacity measured while pressure remains constant
Constant-pressure heat capacity is important because for an ideal gas, Cp is usually larger than Cv because expansion work is included.
What is meant by calorimetry in physical chemistry?
- the experimental measurement of heat changes
- the measurement of bond angles only
- the study of naming inorganic salts
- the determination of atomic number
Show Answer
Answer: the experimental measurement of heat changes
Calorimetry is used to determine heat of reaction, solution, neutralization and combustion.
Which option best explains calorimetry?
- the measurement of bond angles only
- the experimental measurement of heat changes
- the determination of atomic number
- the study of naming inorganic salts
Show Answer
Answer: the experimental measurement of heat changes
The correct concept is: the experimental measurement of heat changes. Calorimetry is used to determine heat of reaction, solution, neutralization and combustion.
A correct statement about calorimetry is:
- the determination of atomic number
- the experimental measurement of heat changes
- the measurement of bond angles only
- the study of naming inorganic salts
Show Answer
Answer: the experimental measurement of heat changes
Calorimetry is important because calorimetry is used to determine heat of reaction, solution, neutralization and combustion.
What is meant by bomb calorimeter in physical chemistry?
- a device for measuring viscosity only
- a constant-volume device used to measure combustion heat
- a constant-pressure open beaker method
- an instrument for measuring wavelength only
Show Answer
Answer: a constant-volume device used to measure combustion heat
Bomb calorimetry is useful for combustion because the reaction occurs in a sealed vessel.
Which option best explains bomb calorimeter?
- a constant-volume device used to measure combustion heat
- a device for measuring viscosity only
- a constant-pressure open beaker method
- an instrument for measuring wavelength only
Show Answer
Answer: a constant-volume device used to measure combustion heat
The correct concept is: a constant-volume device used to measure combustion heat. Bomb calorimetry is useful for combustion because the reaction occurs in a sealed vessel.
A correct statement about bomb calorimeter is:
- an instrument for measuring wavelength only
- a constant-volume device used to measure combustion heat
- a device for measuring viscosity only
- a constant-pressure open beaker method
Show Answer
Answer: a constant-volume device used to measure combustion heat
Bomb calorimeter is important because bomb calorimetry is useful for combustion because the reaction occurs in a sealed vessel.
What is meant by coffee-cup calorimeter in physical chemistry?
- a device used only for gas chromatography
- a simple constant-pressure calorimeter for solution reactions
- a method for measuring molecular mass by titration
- a high-pressure sealed combustion vessel
Show Answer
Answer: a simple constant-pressure calorimeter for solution reactions
It is commonly used for neutralization or dissolution heat measurements in aqueous systems.
Which option best explains coffee-cup calorimeter?
- a method for measuring molecular mass by titration
- a high-pressure sealed combustion vessel
- a device used only for gas chromatography
- a simple constant-pressure calorimeter for solution reactions
Show Answer
Answer: a simple constant-pressure calorimeter for solution reactions
The correct concept is: a simple constant-pressure calorimeter for solution reactions. It is commonly used for neutralization or dissolution heat measurements in aqueous systems.
A correct statement about coffee-cup calorimeter is:
- a device used only for gas chromatography
- a simple constant-pressure calorimeter for solution reactions
- a high-pressure sealed combustion vessel
- a method for measuring molecular mass by titration
Show Answer
Answer: a simple constant-pressure calorimeter for solution reactions
Coffee-cup calorimeter is important because it is commonly used for neutralization or dissolution heat measurements in aqueous systems.
What is meant by thermochemistry in physical chemistry?
- the study of atomic spectra only
- the naming of hydrocarbons
- the study of heat changes in chemical reactions
- the analysis of crystal shapes only
Show Answer
Answer: the study of heat changes in chemical reactions
Thermochemistry applies thermodynamic ideas to chemical transformations.
Which option best explains thermochemistry?
- the naming of hydrocarbons
- the study of heat changes in chemical reactions
- the analysis of crystal shapes only
- the study of atomic spectra only
Show Answer
Answer: the study of heat changes in chemical reactions
The correct concept is: the study of heat changes in chemical reactions. Thermochemistry applies thermodynamic ideas to chemical transformations.
A correct statement about thermochemistry is:
- the analysis of crystal shapes only
- the study of atomic spectra only
- the study of heat changes in chemical reactions
- the naming of hydrocarbons
Show Answer
Answer: the study of heat changes in chemical reactions
Thermochemistry is important because thermochemistry applies thermodynamic ideas to chemical transformations.
What is meant by standard enthalpy change in physical chemistry?
- the heat capacity of one electron
- a rate constant at standard pressure
- enthalpy measured only at absolute zero
- enthalpy change measured under standard-state conditions
Show Answer
Answer: enthalpy change measured under standard-state conditions
Standard enthalpy values allow comparison and calculation of reaction heat effects.
Which option best explains standard enthalpy change?
- a rate constant at standard pressure
- the heat capacity of one electron
- enthalpy change measured under standard-state conditions
- enthalpy measured only at absolute zero
Show Answer
Answer: enthalpy change measured under standard-state conditions
The correct concept is: enthalpy change measured under standard-state conditions. Standard enthalpy values allow comparison and calculation of reaction heat effects.
A correct statement about standard enthalpy change is:
- the heat capacity of one electron
- a rate constant at standard pressure
- enthalpy measured only at absolute zero
- enthalpy change measured under standard-state conditions
Show Answer
Answer: enthalpy change measured under standard-state conditions
Standard enthalpy change is important because standard enthalpy values allow comparison and calculation of reaction heat effects.
What is meant by enthalpy of formation in physical chemistry?
- enthalpy change when one mole of compound forms from elements in standard states
- heat released when a compound breaks into ions only
- the number of bonds in a molecule
- the entropy change of melting
Show Answer
Answer: enthalpy change when one mole of compound forms from elements in standard states
Standard formation enthalpies are used to calculate reaction enthalpies.
Which option best explains enthalpy of formation?
- the entropy change of melting
- enthalpy change when one mole of compound forms from elements in standard states
- the number of bonds in a molecule
- heat released when a compound breaks into ions only
Show Answer
Answer: enthalpy change when one mole of compound forms from elements in standard states
The correct concept is: enthalpy change when one mole of compound forms from elements in standard states. Standard formation enthalpies are used to calculate reaction enthalpies.
A correct statement about enthalpy of formation is:
- the entropy change of melting
- enthalpy change when one mole of compound forms from elements in standard states
- the number of bonds in a molecule
- heat released when a compound breaks into ions only
Show Answer
Answer: enthalpy change when one mole of compound forms from elements in standard states
Enthalpy of formation is important because standard formation enthalpies are used to calculate reaction enthalpies.
What is meant by enthalpy of combustion in physical chemistry?
- a measure of reaction order
- enthalpy change when one mole of substance burns completely in oxygen
- heat absorbed during melting only
- enthalpy change when a gas dissolves in water
Show Answer
Answer: enthalpy change when one mole of substance burns completely in oxygen
Combustion enthalpies are usually negative for fuels because heat is released.
Which option best explains enthalpy of combustion?
- a measure of reaction order
- enthalpy change when one mole of substance burns completely in oxygen
- heat absorbed during melting only
- enthalpy change when a gas dissolves in water
Show Answer
Answer: enthalpy change when one mole of substance burns completely in oxygen
The correct concept is: enthalpy change when one mole of substance burns completely in oxygen. Combustion enthalpies are usually negative for fuels because heat is released.
A correct statement about enthalpy of combustion is:
- enthalpy change when one mole of substance burns completely in oxygen
- enthalpy change when a gas dissolves in water
- a measure of reaction order
- heat absorbed during melting only
Show Answer
Answer: enthalpy change when one mole of substance burns completely in oxygen
Enthalpy of combustion is important because combustion enthalpies are usually negative for fuels because heat is released.
What is meant by enthalpy of neutralization in physical chemistry?
- heat change during sublimation only
- heat change when acid and base react to form one mole of water
- enthalpy of atomizing a metal
- rate of hydrolysis
Show Answer
Answer: heat change when acid and base react to form one mole of water
Strong acid-strong base neutralization has a nearly constant heat value in dilute aqueous solution.
Which option best explains enthalpy of neutralization?
- rate of hydrolysis
- heat change during sublimation only
- enthalpy of atomizing a metal
- heat change when acid and base react to form one mole of water
Show Answer
Answer: heat change when acid and base react to form one mole of water
The correct concept is: heat change when acid and base react to form one mole of water. Strong acid-strong base neutralization has a nearly constant heat value in dilute aqueous solution.
A correct statement about enthalpy of neutralization is:
- heat change when acid and base react to form one mole of water
- rate of hydrolysis
- heat change during sublimation only
- enthalpy of atomizing a metal
Show Answer
Answer: heat change when acid and base react to form one mole of water
Enthalpy of neutralization is important because strong acid-strong base neutralization has a nearly constant heat value in dilute aqueous solution.
What is meant by enthalpy of solution in physical chemistry?
- collision frequency in gases
- enthalpy of combustion in oxygen
- work done in electrolysis only
- heat change when one mole of solute dissolves in solvent
Show Answer
Answer: heat change when one mole of solute dissolves in solvent
Solution enthalpy depends on lattice breaking and solvation interactions.
Which option best explains enthalpy of solution?
- work done in electrolysis only
- enthalpy of combustion in oxygen
- heat change when one mole of solute dissolves in solvent
- collision frequency in gases
Show Answer
Answer: heat change when one mole of solute dissolves in solvent
The correct concept is: heat change when one mole of solute dissolves in solvent. Solution enthalpy depends on lattice breaking and solvation interactions.
A correct statement about enthalpy of solution is:
- enthalpy of combustion in oxygen
- heat change when one mole of solute dissolves in solvent
- work done in electrolysis only
- collision frequency in gases
Show Answer
Answer: heat change when one mole of solute dissolves in solvent
Enthalpy of solution is important because solution enthalpy depends on lattice breaking and solvation interactions.
What is meant by Hess's law in physical chemistry?
- entropy always remains zero
- reaction rate is independent of concentration
- catalysts change equilibrium constants
- overall reaction enthalpy is independent of the route taken
Show Answer
Answer: overall reaction enthalpy is independent of the route taken
Because enthalpy is a state function, reaction enthalpy can be added across steps.
Which option best explains Hess's law?
- entropy always remains zero
- catalysts change equilibrium constants
- reaction rate is independent of concentration
- overall reaction enthalpy is independent of the route taken
Show Answer
Answer: overall reaction enthalpy is independent of the route taken
The correct concept is: overall reaction enthalpy is independent of the route taken. Because enthalpy is a state function, reaction enthalpy can be added across steps.
A correct statement about Hess's law is:
- overall reaction enthalpy is independent of the route taken
- catalysts change equilibrium constants
- entropy always remains zero
- reaction rate is independent of concentration
Show Answer
Answer: overall reaction enthalpy is independent of the route taken
Hess's law is important because because enthalpy is a state function, reaction enthalpy can be added across steps.
What is meant by law of constant heat summation in physical chemistry?
- all reactions have identical heats
- reaction heat depends only on vessel color
- reaction heat is the same whether the reaction occurs in one step or several steps
- heat cannot be measured by calorimetry
Show Answer
Answer: reaction heat is the same whether the reaction occurs in one step or several steps
This is another statement of Hess's law for thermochemical calculations.
Which option best explains law of constant heat summation?
- all reactions have identical heats
- reaction heat is the same whether the reaction occurs in one step or several steps
- heat cannot be measured by calorimetry
- reaction heat depends only on vessel color
Show Answer
Answer: reaction heat is the same whether the reaction occurs in one step or several steps
The correct concept is: reaction heat is the same whether the reaction occurs in one step or several steps. This is another statement of Hess's law for thermochemical calculations.
A correct statement about law of constant heat summation is:
- heat cannot be measured by calorimetry
- reaction heat depends only on vessel color
- all reactions have identical heats
- reaction heat is the same whether the reaction occurs in one step or several steps
Show Answer
Answer: reaction heat is the same whether the reaction occurs in one step or several steps
Law of constant heat summation is important because this is another statement of Hess's law for thermochemical calculations.
What is meant by Kirchhoff's law in thermochemistry in physical chemistry?
- a law that ignores heat capacity
- the pressure dependence of reaction rate only
- a rule for balancing redox equations
- the temperature dependence of reaction enthalpy is related to heat capacity change
Show Answer
Answer: the temperature dependence of reaction enthalpy is related to heat capacity change
Kirchhoff's law helps correct enthalpy values when temperature changes.
Which option best explains Kirchhoff's law in thermochemistry?
- a law that ignores heat capacity
- the temperature dependence of reaction enthalpy is related to heat capacity change
- the pressure dependence of reaction rate only
- a rule for balancing redox equations
Show Answer
Answer: the temperature dependence of reaction enthalpy is related to heat capacity change
The correct concept is: the temperature dependence of reaction enthalpy is related to heat capacity change. Kirchhoff's law helps correct enthalpy values when temperature changes.
A correct statement about Kirchhoff's law in thermochemistry is:
- a law that ignores heat capacity
- the pressure dependence of reaction rate only
- the temperature dependence of reaction enthalpy is related to heat capacity change
- a rule for balancing redox equations
Show Answer
Answer: the temperature dependence of reaction enthalpy is related to heat capacity change
Kirchhoff's law in thermochemistry is important because kirchhoff's law helps correct enthalpy values when temperature changes.
What is meant by bond enthalpy in physical chemistry?
- average enthalpy required to break a chemical bond in the gas phase
- the molecularity of an elementary step
- the rate of a second-order reaction
- entropy gained by freezing
Show Answer
Answer: average enthalpy required to break a chemical bond in the gas phase
Bond enthalpies give approximate estimates of reaction enthalpy.
Which option best explains bond enthalpy?
- the rate of a second-order reaction
- entropy gained by freezing
- average enthalpy required to break a chemical bond in the gas phase
- the molecularity of an elementary step
Show Answer
Answer: average enthalpy required to break a chemical bond in the gas phase
The correct concept is: average enthalpy required to break a chemical bond in the gas phase. Bond enthalpies give approximate estimates of reaction enthalpy.
A correct statement about bond enthalpy is:
- the rate of a second-order reaction
- entropy gained by freezing
- the molecularity of an elementary step
- average enthalpy required to break a chemical bond in the gas phase
Show Answer
Answer: average enthalpy required to break a chemical bond in the gas phase
Bond enthalpy is important because bond enthalpies give approximate estimates of reaction enthalpy.
What is meant by entropy in physical chemistry?
- the concentration of catalyst only
- a value used only in spectroscopy
- a thermodynamic measure of energy dispersal or randomness
- the total mass of a reaction mixture
Show Answer
Answer: a thermodynamic measure of energy dispersal or randomness
Entropy helps describe the number of accessible microscopic arrangements.
Which option best explains entropy?
- the total mass of a reaction mixture
- a value used only in spectroscopy
- a thermodynamic measure of energy dispersal or randomness
- the concentration of catalyst only
Show Answer
Answer: a thermodynamic measure of energy dispersal or randomness
The correct concept is: a thermodynamic measure of energy dispersal or randomness. Entropy helps describe the number of accessible microscopic arrangements.
A correct statement about entropy is:
- the total mass of a reaction mixture
- a value used only in spectroscopy
- the concentration of catalyst only
- a thermodynamic measure of energy dispersal or randomness
Show Answer
Answer: a thermodynamic measure of energy dispersal or randomness
Entropy is important because entropy helps describe the number of accessible microscopic arrangements.
What is meant by entropy change for reversible heat in physical chemistry?
- ΔS = k/t
- ΔS = qrev/T
- ΔS = P/V
- ΔS = mass × volume
Show Answer
Answer: ΔS = qrev/T
Entropy change for a reversible process is heat transferred reversibly divided by absolute temperature.
Which option best explains entropy change for reversible heat?
- ΔS = k/t
- ΔS = P/V
- ΔS = qrev/T
- ΔS = mass × volume
Show Answer
Answer: ΔS = qrev/T
The correct concept is: ΔS = qrev/T. Entropy change for a reversible process is heat transferred reversibly divided by absolute temperature.
A correct statement about entropy change for reversible heat is:
- ΔS = mass × volume
- ΔS = qrev/T
- ΔS = k/t
- ΔS = P/V
Show Answer
Answer: ΔS = qrev/T
Entropy change for reversible heat is important because entropy change for a reversible process is heat transferred reversibly divided by absolute temperature.
What is meant by physical significance of entropy in physical chemistry?
- it indicates the dispersal of energy and tendency toward probable states
- it measures only reaction color
- it tells the name of the compound
- it is the same as molecular weight
Show Answer
Answer: it indicates the dispersal of energy and tendency toward probable states
Higher entropy often corresponds to more accessible microstates.
Which option best explains physical significance of entropy?
- it measures only reaction color
- it is the same as molecular weight
- it tells the name of the compound
- it indicates the dispersal of energy and tendency toward probable states
Show Answer
Answer: it indicates the dispersal of energy and tendency toward probable states
The correct concept is: it indicates the dispersal of energy and tendency toward probable states. Higher entropy often corresponds to more accessible microstates.
A correct statement about physical significance of entropy is:
- it measures only reaction color
- it indicates the dispersal of energy and tendency toward probable states
- it tells the name of the compound
- it is the same as molecular weight
Show Answer
Answer: it indicates the dispersal of energy and tendency toward probable states
Physical significance of entropy is important because higher entropy often corresponds to more accessible microstates.
What is meant by entropy of fusion in physical chemistry?
- rate constant at melting point
- enthalpy change divided by pressure
- entropy change when a solid melts into liquid
- entropy change when gas becomes solid
Show Answer
Answer: entropy change when a solid melts into liquid
Melting usually increases entropy because liquid particles have more freedom than solid particles.
Which option best explains entropy of fusion?
- enthalpy change divided by pressure
- entropy change when a solid melts into liquid
- rate constant at melting point
- entropy change when gas becomes solid
Show Answer
Answer: entropy change when a solid melts into liquid
The correct concept is: entropy change when a solid melts into liquid. Melting usually increases entropy because liquid particles have more freedom than solid particles.
A correct statement about entropy of fusion is:
- rate constant at melting point
- entropy change when a solid melts into liquid
- enthalpy change divided by pressure
- entropy change when gas becomes solid
Show Answer
Answer: entropy change when a solid melts into liquid
Entropy of fusion is important because melting usually increases entropy because liquid particles have more freedom than solid particles.
What is meant by entropy of vaporization in physical chemistry?
- molecularity of evaporation
- entropy change when gas condenses only
- entropy change when a liquid changes into vapor
- work done during filtration
Show Answer
Answer: entropy change when a liquid changes into vapor
Vaporization gives a large entropy increase because gases have much greater freedom.
Which option best explains entropy of vaporization?
- entropy change when a liquid changes into vapor
- molecularity of evaporation
- entropy change when gas condenses only
- work done during filtration
Show Answer
Answer: entropy change when a liquid changes into vapor
The correct concept is: entropy change when a liquid changes into vapor. Vaporization gives a large entropy increase because gases have much greater freedom.
A correct statement about entropy of vaporization is:
- molecularity of evaporation
- entropy change when gas condenses only
- entropy change when a liquid changes into vapor
- work done during filtration
Show Answer
Answer: entropy change when a liquid changes into vapor
Entropy of vaporization is important because vaporization gives a large entropy increase because gases have much greater freedom.
What is meant by entropy change of an ideal gas in physical chemistry?
- entropy changes with temperature and volume or pressure changes
- entropy cannot be calculated for gases
- entropy remains fixed under all conditions
- entropy depends only on color
Show Answer
Answer: entropy changes with temperature and volume or pressure changes
For ideal gases, entropy increases with expansion and heating.
Which option best explains entropy change of an ideal gas?
- entropy cannot be calculated for gases
- entropy remains fixed under all conditions
- entropy depends only on color
- entropy changes with temperature and volume or pressure changes
Show Answer
Answer: entropy changes with temperature and volume or pressure changes
The correct concept is: entropy changes with temperature and volume or pressure changes. For ideal gases, entropy increases with expansion and heating.
A correct statement about entropy change of an ideal gas is:
- entropy depends only on color
- entropy cannot be calculated for gases
- entropy remains fixed under all conditions
- entropy changes with temperature and volume or pressure changes
Show Answer
Answer: entropy changes with temperature and volume or pressure changes
Entropy change of an ideal gas is important because for ideal gases, entropy increases with expansion and heating.
What is meant by Carnot cycle in physical chemistry?
- a method for weighing gases
- a mechanism for enzyme reactions only
- a sequence of irreversible titration steps
- an ideal reversible cycle operating between two temperatures
Show Answer
Answer: an ideal reversible cycle operating between two temperatures
The Carnot cycle sets the maximum possible efficiency for a heat engine.
Which option best explains Carnot cycle?
- a sequence of irreversible titration steps
- a mechanism for enzyme reactions only
- a method for weighing gases
- an ideal reversible cycle operating between two temperatures
Show Answer
Answer: an ideal reversible cycle operating between two temperatures
The correct concept is: an ideal reversible cycle operating between two temperatures. The Carnot cycle sets the maximum possible efficiency for a heat engine.
A correct statement about Carnot cycle is:
- a sequence of irreversible titration steps
- an ideal reversible cycle operating between two temperatures
- a mechanism for enzyme reactions only
- a method for weighing gases
Show Answer
Answer: an ideal reversible cycle operating between two temperatures
Carnot cycle is important because the Carnot cycle sets the maximum possible efficiency for a heat engine.
What is meant by Carnot efficiency in physical chemistry?
- efficiency always equal to 100 percent
- efficiency unrelated to temperature
- efficiency depending only on catalyst amount
- the maximum efficiency depending only on hot and cold reservoir temperatures
Show Answer
Answer: the maximum efficiency depending only on hot and cold reservoir temperatures
A heat engine cannot exceed the Carnot efficiency between the same reservoirs.
Which option best explains Carnot efficiency?
- efficiency always equal to 100 percent
- efficiency unrelated to temperature
- efficiency depending only on catalyst amount
- the maximum efficiency depending only on hot and cold reservoir temperatures
Show Answer
Answer: the maximum efficiency depending only on hot and cold reservoir temperatures
The correct concept is: the maximum efficiency depending only on hot and cold reservoir temperatures. A heat engine cannot exceed the Carnot efficiency between the same reservoirs.
A correct statement about Carnot efficiency is:
- efficiency depending only on catalyst amount
- the maximum efficiency depending only on hot and cold reservoir temperatures
- efficiency unrelated to temperature
- efficiency always equal to 100 percent
Show Answer
Answer: the maximum efficiency depending only on hot and cold reservoir temperatures
Carnot efficiency is important because a heat engine cannot exceed the Carnot efficiency between the same reservoirs.
What is meant by reversible process in physical chemistry?
- an ideal process that can be reversed by infinitesimal changes
- a process with large friction losses
- a process where all molecules stop moving
- a process that cannot be undone in any way
Show Answer
Answer: an ideal process that can be reversed by infinitesimal changes
A reversible process proceeds through equilibrium states and gives maximum work.
Which option best explains reversible process?
- a process where all molecules stop moving
- an ideal process that can be reversed by infinitesimal changes
- a process with large friction losses
- a process that cannot be undone in any way
Show Answer
Answer: an ideal process that can be reversed by infinitesimal changes
The correct concept is: an ideal process that can be reversed by infinitesimal changes. A reversible process proceeds through equilibrium states and gives maximum work.
A correct statement about reversible process is:
- a process that cannot be undone in any way
- a process with large friction losses
- a process where all molecules stop moving
- an ideal process that can be reversed by infinitesimal changes
Show Answer
Answer: an ideal process that can be reversed by infinitesimal changes
Reversible process is important because a reversible process proceeds through equilibrium states and gives maximum work.
What is meant by irreversible process in physical chemistry?
- a real process involving finite driving forces or dissipative effects
- a process found only in mathematical symbols
- an ideal process with no entropy production
- a process requiring perfect equilibrium at every step
Show Answer
Answer: a real process involving finite driving forces or dissipative effects
Most natural processes are irreversible due to friction, mixing or unrestrained expansion.
Which option best explains irreversible process?
- a process found only in mathematical symbols
- a process requiring perfect equilibrium at every step
- a real process involving finite driving forces or dissipative effects
- an ideal process with no entropy production
Show Answer
Answer: a real process involving finite driving forces or dissipative effects
The correct concept is: a real process involving finite driving forces or dissipative effects. Most natural processes are irreversible due to friction, mixing or unrestrained expansion.
A correct statement about irreversible process is:
- an ideal process with no entropy production
- a process found only in mathematical symbols
- a process requiring perfect equilibrium at every step
- a real process involving finite driving forces or dissipative effects
Show Answer
Answer: a real process involving finite driving forces or dissipative effects
Irreversible process is important because most natural processes are irreversible due to friction, mixing or unrestrained expansion.
What is meant by nonspontaneous process in physical chemistry?
- a process that always happens instantly
- a process that requires continuous external input under given conditions
- a process that violates mass conservation
- a process with no energy interaction
Show Answer
Answer: a process that requires continuous external input under given conditions
Nonspontaneous changes do not occur on their own in the specified direction.
Which option best explains nonspontaneous process?
- a process that always happens instantly
- a process that violates mass conservation
- a process that requires continuous external input under given conditions
- a process with no energy interaction
Show Answer
Answer: a process that requires continuous external input under given conditions
The correct concept is: a process that requires continuous external input under given conditions. Nonspontaneous changes do not occur on their own in the specified direction.
A correct statement about nonspontaneous process is:
- a process that always happens instantly
- a process that requires continuous external input under given conditions
- a process with no energy interaction
- a process that violates mass conservation
Show Answer
Answer: a process that requires continuous external input under given conditions
Nonspontaneous process is important because nonspontaneous changes do not occur on their own in the specified direction.
What is meant by universe entropy criterion in physical chemistry?
- a process is spontaneous if ΔSuniverse is positive
- a process is spontaneous only if ΔU is zero
- a process is spontaneous only if concentration is one
- a process is spontaneous only if pressure is zero
Show Answer
Answer: a process is spontaneous if ΔSuniverse is positive
The second law uses the entropy change of system plus surroundings to judge spontaneity.
Which option best explains universe entropy criterion?
- a process is spontaneous only if ΔU is zero
- a process is spontaneous only if concentration is one
- a process is spontaneous if ΔSuniverse is positive
- a process is spontaneous only if pressure is zero
Show Answer
Answer: a process is spontaneous if ΔSuniverse is positive
The correct concept is: a process is spontaneous if ΔSuniverse is positive. The second law uses the entropy change of system plus surroundings to judge spontaneity.
A correct statement about universe entropy criterion is:
- a process is spontaneous only if concentration is one
- a process is spontaneous only if pressure is zero
- a process is spontaneous only if ΔU is zero
- a process is spontaneous if ΔSuniverse is positive
Show Answer
Answer: a process is spontaneous if ΔSuniverse is positive
Universe entropy criterion is important because the second law uses the entropy change of system plus surroundings to judge spontaneity.
What is meant by Gibbs free energy in physical chemistry?
- a state function used to predict spontaneity at constant temperature and pressure
- a property used only for naming salts
- a measure of atomic mass
- a path function equal to heat only
Show Answer
Answer: a state function used to predict spontaneity at constant temperature and pressure
At constant temperature and pressure, negative ΔG indicates a spontaneous direction.
Which option best explains Gibbs free energy?
- a path function equal to heat only
- a property used only for naming salts
- a state function used to predict spontaneity at constant temperature and pressure
- a measure of atomic mass
Show Answer
Answer: a state function used to predict spontaneity at constant temperature and pressure
The correct concept is: a state function used to predict spontaneity at constant temperature and pressure. At constant temperature and pressure, negative ΔG indicates a spontaneous direction.
A correct statement about Gibbs free energy is:
- a path function equal to heat only
- a measure of atomic mass
- a property used only for naming salts
- a state function used to predict spontaneity at constant temperature and pressure
Show Answer
Answer: a state function used to predict spontaneity at constant temperature and pressure
Gibbs free energy is important because at constant temperature and pressure, negative ΔG indicates a spontaneous direction.
What is meant by Gibbs equation in physical chemistry?
- ΔG = ΔH – TΔS
- ΔG = k[A]^n
- ΔG = PV/nRT
- ΔG = ΔH + TΔS
Show Answer
Answer: ΔG = ΔH – TΔS
This equation links free energy with enthalpy, temperature and entropy.
Which option best explains Gibbs equation?
- ΔG = ΔH – TΔS
- ΔG = ΔH + TΔS
- ΔG = PV/nRT
- ΔG = k[A]^n
Show Answer
Answer: ΔG = ΔH – TΔS
The correct concept is: ΔG = ΔH – TΔS. This equation links free energy with enthalpy, temperature and entropy.
A correct statement about Gibbs equation is:
- ΔG = ΔH – TΔS
- ΔG = k[A]^n
- ΔG = PV/nRT
- ΔG = ΔH + TΔS
Show Answer
Answer: ΔG = ΔH – TΔS
Gibbs equation is important because this equation links free energy with enthalpy, temperature and entropy.
What is meant by negative ΔG in physical chemistry?
- a sign that no molecules collide
- a sign that a process is thermodynamically spontaneous under given conditions
- a sign of zero entropy always
- a sign that reaction is impossible at all temperatures
Show Answer
Answer: a sign that a process is thermodynamically spontaneous under given conditions
Negative Gibbs free energy change indicates the forward direction is favored.
Which option best explains negative ΔG?
- a sign that reaction is impossible at all temperatures
- a sign of zero entropy always
- a sign that no molecules collide
- a sign that a process is thermodynamically spontaneous under given conditions
Show Answer
Answer: a sign that a process is thermodynamically spontaneous under given conditions
The correct concept is: a sign that a process is thermodynamically spontaneous under given conditions. Negative Gibbs free energy change indicates the forward direction is favored.
A correct statement about negative ΔG is:
- a sign that no molecules collide
- a sign that a process is thermodynamically spontaneous under given conditions
- a sign of zero entropy always
- a sign that reaction is impossible at all temperatures
Show Answer
Answer: a sign that a process is thermodynamically spontaneous under given conditions
Negative δg is important because negative Gibbs free energy change indicates the forward direction is favored.
What is meant by positive ΔG in physical chemistry?
- a sign that the forward process is nonspontaneous under given conditions
- a sign of equilibrium only
- a sign that enthalpy must be zero
- a sign that the process must be instant
Show Answer
Answer: a sign that the forward process is nonspontaneous under given conditions
A positive ΔG means external work or coupling may be needed to drive the process forward.
Which option best explains positive ΔG?
- a sign that the process must be instant
- a sign of equilibrium only
- a sign that the forward process is nonspontaneous under given conditions
- a sign that enthalpy must be zero
Show Answer
Answer: a sign that the forward process is nonspontaneous under given conditions
The correct concept is: a sign that the forward process is nonspontaneous under given conditions. A positive ΔG means external work or coupling may be needed to drive the process forward.
A correct statement about positive ΔG is:
- a sign of equilibrium only
- a sign that enthalpy must be zero
- a sign that the forward process is nonspontaneous under given conditions
- a sign that the process must be instant
Show Answer
Answer: a sign that the forward process is nonspontaneous under given conditions
Positive δg is important because a positive ΔG means external work or coupling may be needed to drive the process forward.
What is meant by ΔG at equilibrium in physical chemistry?
- always strongly negative
- always equal to activation energy
- zero for a system at equilibrium
- equal to molecularity
Show Answer
Answer: zero for a system at equilibrium
At equilibrium, there is no net thermodynamic driving force in either direction.
Which option best explains ΔG at equilibrium?
- equal to molecularity
- always strongly negative
- zero for a system at equilibrium
- always equal to activation energy
Show Answer
Answer: zero for a system at equilibrium
The correct concept is: zero for a system at equilibrium. At equilibrium, there is no net thermodynamic driving force in either direction.
A correct statement about ΔG at equilibrium is:
- equal to molecularity
- zero for a system at equilibrium
- always equal to activation energy
- always strongly negative
Show Answer
Answer: zero for a system at equilibrium
Δg at equilibrium is important because at equilibrium, there is no net thermodynamic driving force in either direction.
What is meant by relation between ΔG° and equilibrium constant in physical chemistry?
- ΔG° = q + w
- ΔG° = RTK
- K = Ea/RT
- ΔG° = -RT ln K
Show Answer
Answer: ΔG° = -RT ln K
This relation connects thermodynamic driving force with equilibrium composition.
Which option best explains relation between ΔG° and equilibrium constant?
- K = Ea/RT
- ΔG° = RTK
- ΔG° = -RT ln K
- ΔG° = q + w
Show Answer
Answer: ΔG° = -RT ln K
The correct concept is: ΔG° = -RT ln K. This relation connects thermodynamic driving force with equilibrium composition.
A correct statement about relation between ΔG° and equilibrium constant is:
- ΔG° = RTK
- ΔG° = q + w
- ΔG° = -RT ln K
- K = Ea/RT
Show Answer
Answer: ΔG° = -RT ln K
Relation between δg° and equilibrium constant is important because this relation connects thermodynamic driving force with equilibrium composition.
What is meant by equilibrium constant in physical chemistry?
- a value expressing the ratio of product and reactant activities at equilibrium
- a value that always equals reaction rate
- a value unrelated to temperature
- a value that changes when a catalyst is added
Show Answer
Answer: a value expressing the ratio of product and reactant activities at equilibrium
The equilibrium constant describes the position of equilibrium for a reaction at a fixed temperature.
Which option best explains equilibrium constant?
- a value that always equals reaction rate
- a value that changes when a catalyst is added
- a value unrelated to temperature
- a value expressing the ratio of product and reactant activities at equilibrium
Show Answer
Answer: a value expressing the ratio of product and reactant activities at equilibrium
The correct concept is: a value expressing the ratio of product and reactant activities at equilibrium. The equilibrium constant describes the position of equilibrium for a reaction at a fixed temperature.
A correct statement about equilibrium constant is:
- a value that changes when a catalyst is added
- a value unrelated to temperature
- a value expressing the ratio of product and reactant activities at equilibrium
- a value that always equals reaction rate
Show Answer
Answer: a value expressing the ratio of product and reactant activities at equilibrium
Equilibrium constant is important because the equilibrium constant describes the position of equilibrium for a reaction at a fixed temperature.
What is meant by Gibbs-Helmholtz equation in physical chemistry?
- a rule for writing Lewis structures
- a relation showing how Gibbs free energy changes with temperature
- an equation for only zero-order kinetics
- a statement that entropy is always zero
Show Answer
Answer: a relation showing how Gibbs free energy changes with temperature
It is useful for analyzing temperature dependence of free energy and equilibrium.
Which option best explains Gibbs-Helmholtz equation?
- an equation for only zero-order kinetics
- a relation showing how Gibbs free energy changes with temperature
- a statement that entropy is always zero
- a rule for writing Lewis structures
Show Answer
Answer: a relation showing how Gibbs free energy changes with temperature
The correct concept is: a relation showing how Gibbs free energy changes with temperature. It is useful for analyzing temperature dependence of free energy and equilibrium.
A correct statement about Gibbs-Helmholtz equation is:
- a rule for writing Lewis structures
- an equation for only zero-order kinetics
- a statement that entropy is always zero
- a relation showing how Gibbs free energy changes with temperature
Show Answer
Answer: a relation showing how Gibbs free energy changes with temperature
Gibbs-helmholtz equation is important because it is useful for analyzing temperature dependence of free energy and equilibrium.
What is meant by Clausius-Clapeyron equation in physical chemistry?
- a formula for density of solids only
- an equation relating vapor pressure changes to temperature and enthalpy of phase change
- an equation for acid-base titration only
- a law for determining reaction order by half-life
Show Answer
Answer: an equation relating vapor pressure changes to temperature and enthalpy of phase change
It is commonly applied to liquid-vapor equilibrium and vapor pressure data.
Which option best explains Clausius-Clapeyron equation?
- an equation relating vapor pressure changes to temperature and enthalpy of phase change
- a law for determining reaction order by half-life
- a formula for density of solids only
- an equation for acid-base titration only
Show Answer
Answer: an equation relating vapor pressure changes to temperature and enthalpy of phase change
The correct concept is: an equation relating vapor pressure changes to temperature and enthalpy of phase change. It is commonly applied to liquid-vapor equilibrium and vapor pressure data.
A correct statement about Clausius-Clapeyron equation is:
- a law for determining reaction order by half-life
- an equation relating vapor pressure changes to temperature and enthalpy of phase change
- an equation for acid-base titration only
- a formula for density of solids only
Show Answer
Answer: an equation relating vapor pressure changes to temperature and enthalpy of phase change
Clausius-clapeyron equation is important because it is commonly applied to liquid-vapor equilibrium and vapor pressure data.
What is meant by fugacity in physical chemistry?
- the actual color of a gas
- a measure of bond length only
- a constant equal to heat capacity
- an effective pressure used to describe non-ideal gases
Show Answer
Answer: an effective pressure used to describe non-ideal gases
Fugacity corrects ideal gas behavior when real gas interactions become important.
Which option best explains fugacity?
- an effective pressure used to describe non-ideal gases
- a measure of bond length only
- the actual color of a gas
- a constant equal to heat capacity
Show Answer
Answer: an effective pressure used to describe non-ideal gases
The correct concept is: an effective pressure used to describe non-ideal gases. Fugacity corrects ideal gas behavior when real gas interactions become important.
A correct statement about fugacity is:
- a measure of bond length only
- the actual color of a gas
- an effective pressure used to describe non-ideal gases
- a constant equal to heat capacity
Show Answer
Answer: an effective pressure used to describe non-ideal gases
Fugacity is important because fugacity corrects ideal gas behavior when real gas interactions become important.
What is meant by activity in physical chemistry?
- a synonym for activation energy
- the stirring speed of a solution
- the exact mass of the container
- an effective concentration used in non-ideal solutions
Show Answer
Answer: an effective concentration used in non-ideal solutions
Activity accounts for deviations from ideal solution behavior.
Which option best explains activity?
- an effective concentration used in non-ideal solutions
- the stirring speed of a solution
- the exact mass of the container
- a synonym for activation energy
Show Answer
Answer: an effective concentration used in non-ideal solutions
The correct concept is: an effective concentration used in non-ideal solutions. Activity accounts for deviations from ideal solution behavior.
A correct statement about activity is:
- an effective concentration used in non-ideal solutions
- the stirring speed of a solution
- the exact mass of the container
- a synonym for activation energy
Show Answer
Answer: an effective concentration used in non-ideal solutions
Activity is important because activity accounts for deviations from ideal solution behavior.
What is meant by chemical potential in physical chemistry?
- the total molecular weight of a mixture
- the shape of a beaker
- the kinetic energy of a single collision
- the partial molar Gibbs free energy of a component
Show Answer
Answer: the partial molar Gibbs free energy of a component
Chemical potential indicates the tendency of a substance to move or react.
Which option best explains chemical potential?
- the kinetic energy of a single collision
- the shape of a beaker
- the partial molar Gibbs free energy of a component
- the total molecular weight of a mixture
Show Answer
Answer: the partial molar Gibbs free energy of a component
The correct concept is: the partial molar Gibbs free energy of a component. Chemical potential indicates the tendency of a substance to move or react.
A correct statement about chemical potential is:
- the kinetic energy of a single collision
- the total molecular weight of a mixture
- the partial molar Gibbs free energy of a component
- the shape of a beaker
Show Answer
Answer: the partial molar Gibbs free energy of a component
Chemical potential is important because chemical potential indicates the tendency of a substance to move or react.
What is meant by chemical kinetics in physical chemistry?
- the study of heat capacity only
- the naming of coordination compounds
- the study of reaction rates and mechanisms
- the study of equilibrium positions only
Show Answer
Answer: the study of reaction rates and mechanisms
Kinetics explains how fast reactions occur and what steps may be involved.
Which option best explains chemical kinetics?
- the study of equilibrium positions only
- the naming of coordination compounds
- the study of reaction rates and mechanisms
- the study of heat capacity only
Show Answer
Answer: the study of reaction rates and mechanisms
The correct concept is: the study of reaction rates and mechanisms. Kinetics explains how fast reactions occur and what steps may be involved.
A correct statement about chemical kinetics is:
- the study of equilibrium positions only
- the study of heat capacity only
- the study of reaction rates and mechanisms
- the naming of coordination compounds
Show Answer
Answer: the study of reaction rates and mechanisms
Chemical kinetics is important because kinetics explains how fast reactions occur and what steps may be involved.
What is meant by reaction rate in physical chemistry?
- the molecular weight of a product
- the pressure of a solid sample
- the total enthalpy of a reaction
- the change in concentration of reactant or product per unit time
Show Answer
Answer: the change in concentration of reactant or product per unit time
Reaction rate measures how quickly a chemical change proceeds.
Which option best explains reaction rate?
- the pressure of a solid sample
- the change in concentration of reactant or product per unit time
- the total enthalpy of a reaction
- the molecular weight of a product
Show Answer
Answer: the change in concentration of reactant or product per unit time
The correct concept is: the change in concentration of reactant or product per unit time. Reaction rate measures how quickly a chemical change proceeds.
A correct statement about reaction rate is:
- the pressure of a solid sample
- the total enthalpy of a reaction
- the change in concentration of reactant or product per unit time
- the molecular weight of a product
Show Answer
Answer: the change in concentration of reactant or product per unit time
Reaction rate is important because reaction rate measures how quickly a chemical change proceeds.
What is meant by rate law in physical chemistry?
- an equation relating reaction rate to reactant concentrations
- a statement of Hess's law
- a table of safety symbols
- an equation that balances atoms only
Show Answer
Answer: an equation relating reaction rate to reactant concentrations
A rate law is usually determined experimentally.
Which option best explains rate law?
- a statement of Hess's law
- a table of safety symbols
- an equation that balances atoms only
- an equation relating reaction rate to reactant concentrations
Show Answer
Answer: an equation relating reaction rate to reactant concentrations
The correct concept is: an equation relating reaction rate to reactant concentrations. A rate law is usually determined experimentally.
A correct statement about rate law is:
- a table of safety symbols
- an equation relating reaction rate to reactant concentrations
- a statement of Hess's law
- an equation that balances atoms only
Show Answer
Answer: an equation relating reaction rate to reactant concentrations
Rate law is important because a rate law is usually determined experimentally.
What is meant by rate constant in physical chemistry?
- the proportionality constant in a rate law
- a value independent of temperature for all reactions
- the total heat absorbed
- the concentration of product at equilibrium
Show Answer
Answer: the proportionality constant in a rate law
The rate constant depends on temperature and the nature of the reaction.
Which option best explains rate constant?
- the proportionality constant in a rate law
- the concentration of product at equilibrium
- the total heat absorbed
- a value independent of temperature for all reactions
Show Answer
Answer: the proportionality constant in a rate law
The correct concept is: the proportionality constant in a rate law. The rate constant depends on temperature and the nature of the reaction.
A correct statement about rate constant is:
- the proportionality constant in a rate law
- the concentration of product at equilibrium
- the total heat absorbed
- a value independent of temperature for all reactions
Show Answer
Answer: the proportionality constant in a rate law
Rate constant is important because the rate constant depends on temperature and the nature of the reaction.
What is meant by order of reaction in physical chemistry?
- the total number of reaction vessels
- the sequence of topics in a syllabus
- the number of atoms in the product
- the sum of powers of concentration terms in the rate law
Show Answer
Answer: the sum of powers of concentration terms in the rate law
Reaction order is obtained from experimental rate data, not directly from the balanced equation in most cases.
Which option best explains order of reaction?
- the sum of powers of concentration terms in the rate law
- the sequence of topics in a syllabus
- the total number of reaction vessels
- the number of atoms in the product
Show Answer
Answer: the sum of powers of concentration terms in the rate law
The correct concept is: the sum of powers of concentration terms in the rate law. Reaction order is obtained from experimental rate data, not directly from the balanced equation in most cases.
A correct statement about order of reaction is:
- the total number of reaction vessels
- the sum of powers of concentration terms in the rate law
- the sequence of topics in a syllabus
- the number of atoms in the product
Show Answer
Answer: the sum of powers of concentration terms in the rate law
Order of reaction is important because reaction order is obtained from experimental rate data, not directly from the balanced equation in most cases.
What is meant by zero-order reaction in physical chemistry?
- a reaction whose rate depends on concentration squared
- a reaction whose rate is independent of reactant concentration
- a reaction with no products
- a reaction impossible to measure
Show Answer
Answer: a reaction whose rate is independent of reactant concentration
Zero-order behavior may occur on saturated catalyst surfaces or under special conditions.
Which option best explains zero-order reaction?
- a reaction with no products
- a reaction whose rate depends on concentration squared
- a reaction impossible to measure
- a reaction whose rate is independent of reactant concentration
Show Answer
Answer: a reaction whose rate is independent of reactant concentration
The correct concept is: a reaction whose rate is independent of reactant concentration. Zero-order behavior may occur on saturated catalyst surfaces or under special conditions.
A correct statement about zero-order reaction is:
- a reaction whose rate depends on concentration squared
- a reaction impossible to measure
- a reaction whose rate is independent of reactant concentration
- a reaction with no products
Show Answer
Answer: a reaction whose rate is independent of reactant concentration
Zero-order reaction is important because zero-order behavior may occur on saturated catalyst surfaces or under special conditions.
What is meant by first-order reaction in physical chemistry?
- a reaction whose rate is independent of concentration
- a reaction with rate proportional to concentration squared
- a reaction whose rate is directly proportional to one reactant concentration
- a reaction with no half-life
Show Answer
Answer: a reaction whose rate is directly proportional to one reactant concentration
Radioactive decay and many decompositions follow first-order kinetics.
Which option best explains first-order reaction?
- a reaction whose rate is independent of concentration
- a reaction with no half-life
- a reaction whose rate is directly proportional to one reactant concentration
- a reaction with rate proportional to concentration squared
Show Answer
Answer: a reaction whose rate is directly proportional to one reactant concentration
The correct concept is: a reaction whose rate is directly proportional to one reactant concentration. Radioactive decay and many decompositions follow first-order kinetics.
A correct statement about first-order reaction is:
- a reaction with no half-life
- a reaction whose rate is directly proportional to one reactant concentration
- a reaction with rate proportional to concentration squared
- a reaction whose rate is independent of concentration
Show Answer
Answer: a reaction whose rate is directly proportional to one reactant concentration
First-order reaction is important because radioactive decay and many decompositions follow first-order kinetics.
What is meant by second-order reaction in physical chemistry?
- a reaction that cannot have a rate law
- a reaction with overall rate order equal to two
- a reaction with order always equal to molecularity in complex mechanisms
- a reaction with no dependence on concentration
Show Answer
Answer: a reaction with overall rate order equal to two
Second-order reactions may involve one reactant squared or two first-power reactants.
Which option best explains second-order reaction?
- a reaction with overall rate order equal to two
- a reaction that cannot have a rate law
- a reaction with no dependence on concentration
- a reaction with order always equal to molecularity in complex mechanisms
Show Answer
Answer: a reaction with overall rate order equal to two
The correct concept is: a reaction with overall rate order equal to two. Second-order reactions may involve one reactant squared or two first-power reactants.
A correct statement about second-order reaction is:
- a reaction that cannot have a rate law
- a reaction with overall rate order equal to two
- a reaction with order always equal to molecularity in complex mechanisms
- a reaction with no dependence on concentration
Show Answer
Answer: a reaction with overall rate order equal to two
Second-order reaction is important because second-order reactions may involve one reactant squared or two first-power reactants.
What is meant by third-order reaction in physical chemistry?
- a reaction where only three products are formed
- a reaction where temperature is always zero
- a reaction with overall rate order equal to three
- a reaction that must be instantaneous
Show Answer
Answer: a reaction with overall rate order equal to three
Third-order kinetics can involve combinations of concentration powers summing to three.
Which option best explains third-order reaction?
- a reaction where temperature is always zero
- a reaction with overall rate order equal to three
- a reaction where only three products are formed
- a reaction that must be instantaneous
Show Answer
Answer: a reaction with overall rate order equal to three
The correct concept is: a reaction with overall rate order equal to three. Third-order kinetics can involve combinations of concentration powers summing to three.
A correct statement about third-order reaction is:
- a reaction that must be instantaneous
- a reaction where only three products are formed
- a reaction where temperature is always zero
- a reaction with overall rate order equal to three
Show Answer
Answer: a reaction with overall rate order equal to three
Third-order reaction is important because third-order kinetics can involve combinations of concentration powers summing to three.
What is meant by overall order in physical chemistry?
- the number of reaction arrows in a mechanism
- the total exponent sum in the experimentally determined rate law
- the alphabetical order of chemicals
- the total number of atoms in reactants
Show Answer
Answer: the total exponent sum in the experimentally determined rate law
Overall order controls the units of the rate constant and concentration dependence of rate.
Which option best explains overall order?
- the total exponent sum in the experimentally determined rate law
- the total number of atoms in reactants
- the number of reaction arrows in a mechanism
- the alphabetical order of chemicals
Show Answer
Answer: the total exponent sum in the experimentally determined rate law
The correct concept is: the total exponent sum in the experimentally determined rate law. Overall order controls the units of the rate constant and concentration dependence of rate.
A correct statement about overall order is:
- the number of reaction arrows in a mechanism
- the total exponent sum in the experimentally determined rate law
- the total number of atoms in reactants
- the alphabetical order of chemicals
Show Answer
Answer: the total exponent sum in the experimentally determined rate law
Overall order is important because overall order controls the units of the rate constant and concentration dependence of rate.
What is meant by integrated rate law in physical chemistry?
- a rate expression showing concentration as a function of time
- a rule for balancing equations by inspection
- a table listing atomic masses
- a law connecting ΔH with temperature only
Show Answer
Answer: a rate expression showing concentration as a function of time
Integrated laws help determine order and predict concentration at different times.
Which option best explains integrated rate law?
- a rate expression showing concentration as a function of time
- a table listing atomic masses
- a law connecting ΔH with temperature only
- a rule for balancing equations by inspection
Show Answer
Answer: a rate expression showing concentration as a function of time
The correct concept is: a rate expression showing concentration as a function of time. Integrated laws help determine order and predict concentration at different times.
A correct statement about integrated rate law is:
- a table listing atomic masses
- a rule for balancing equations by inspection
- a law connecting ΔH with temperature only
- a rate expression showing concentration as a function of time
Show Answer
Answer: a rate expression showing concentration as a function of time
Integrated rate law is important because integrated laws help determine order and predict concentration at different times.
What is meant by zero-order integrated law in physical chemistry?
- ln[A]t = ln[A]0 – kt
- k = Ae^(-Ea/RT)
- [A]t = [A]0 – kt
- 1/[A]t = 1/[A]0 + kt
Show Answer
Answer: [A]t = [A]0 – kt
A plot of concentration versus time is linear for zero-order reactions.
Which option best explains zero-order integrated law?
- ln[A]t = ln[A]0 – kt
- k = Ae^(-Ea/RT)
- [A]t = [A]0 – kt
- 1/[A]t = 1/[A]0 + kt
Show Answer
Answer: [A]t = [A]0 – kt
The correct concept is: [A]t = [A]0 – kt. A plot of concentration versus time is linear for zero-order reactions.
A correct statement about zero-order integrated law is:
- k = Ae^(-Ea/RT)
- 1/[A]t = 1/[A]0 + kt
- [A]t = [A]0 – kt
- ln[A]t = ln[A]0 – kt
Show Answer
Answer: [A]t = [A]0 – kt
Zero-order integrated law is important because a plot of concentration versus time is linear for zero-order reactions.
What is meant by first-order integrated law in physical chemistry?
- ln[A]t = ln[A]0 – kt
- q = mCΔT
- 1/[A]t = 1/[A]0 + kt
- [A]t = [A]0 – kt
Show Answer
Answer: ln[A]t = ln[A]0 – kt
A plot of ln concentration versus time is linear for first-order reactions.
Which option best explains first-order integrated law?
- q = mCΔT
- ln[A]t = ln[A]0 – kt
- 1/[A]t = 1/[A]0 + kt
- [A]t = [A]0 – kt
Show Answer
Answer: ln[A]t = ln[A]0 – kt
The correct concept is: ln[A]t = ln[A]0 – kt. A plot of ln concentration versus time is linear for first-order reactions.
A correct statement about first-order integrated law is:
- ln[A]t = ln[A]0 – kt
- [A]t = [A]0 – kt
- 1/[A]t = 1/[A]0 + kt
- q = mCΔT
Show Answer
Answer: ln[A]t = ln[A]0 – kt
First-order integrated law is important because a plot of ln concentration versus time is linear for first-order reactions.
What is meant by second-order integrated law in physical chemistry?
- ΔG = ΔH – TΔS
- [A]t = [A]0 – kt
- ln[A]t = ln[A]0 – kt
- 1/[A]t = 1/[A]0 + kt
Show Answer
Answer: 1/[A]t = 1/[A]0 + kt
For a simple second-order reaction in one reactant, inverse concentration versus time is linear.
Which option best explains second-order integrated law?
- 1/[A]t = 1/[A]0 + kt
- [A]t = [A]0 – kt
- ΔG = ΔH – TΔS
- ln[A]t = ln[A]0 – kt
Show Answer
Answer: 1/[A]t = 1/[A]0 + kt
The correct concept is: 1/[A]t = 1/[A]0 + kt. For a simple second-order reaction in one reactant, inverse concentration versus time is linear.
A correct statement about second-order integrated law is:
- ΔG = ΔH – TΔS
- ln[A]t = ln[A]0 – kt
- 1/[A]t = 1/[A]0 + kt
- [A]t = [A]0 – kt
Show Answer
Answer: 1/[A]t = 1/[A]0 + kt
Second-order integrated law is important because for a simple second-order reaction in one reactant, inverse concentration versus time is linear.
What is meant by half-life in physical chemistry?
- the time needed to double the equilibrium constant
- the time required for reactant concentration to fall to half its initial value
- the pressure at half volume only
- the temperature at which entropy is zero
Show Answer
Answer: the time required for reactant concentration to fall to half its initial value
Half-life is a useful kinetic measure and depends on order of reaction.
Which option best explains half-life?
- the time needed to double the equilibrium constant
- the time required for reactant concentration to fall to half its initial value
- the temperature at which entropy is zero
- the pressure at half volume only
Show Answer
Answer: the time required for reactant concentration to fall to half its initial value
The correct concept is: the time required for reactant concentration to fall to half its initial value. Half-life is a useful kinetic measure and depends on order of reaction.
A correct statement about half-life is:
- the temperature at which entropy is zero
- the pressure at half volume only
- the time required for reactant concentration to fall to half its initial value
- the time needed to double the equilibrium constant
Show Answer
Answer: the time required for reactant concentration to fall to half its initial value
Half-life is important because half-life is a useful kinetic measure and depends on order of reaction.
What is meant by zero-order half-life in physical chemistry?
- t1/2 = 0.693/k
- t1/2 = 1/(k[A]0)
- t1/2 = [A]0/(2k)
- t1/2 = RT ln K
Show Answer
Answer: t1/2 = [A]0/(2k)
For zero-order reactions, half-life decreases as reactant concentration decreases.
Which option best explains zero-order half-life?
- t1/2 = 1/(k[A]0)
- t1/2 = 0.693/k
- t1/2 = [A]0/(2k)
- t1/2 = RT ln K
Show Answer
Answer: t1/2 = [A]0/(2k)
The correct concept is: t1/2 = [A]0/(2k). For zero-order reactions, half-life decreases as reactant concentration decreases.
A correct statement about zero-order half-life is:
- t1/2 = 1/(k[A]0)
- t1/2 = [A]0/(2k)
- t1/2 = RT ln K
- t1/2 = 0.693/k
Show Answer
Answer: t1/2 = [A]0/(2k)
Zero-order half-life is important because for zero-order reactions, half-life decreases as reactant concentration decreases.
What is meant by first-order half-life in physical chemistry?
- t1/2 = qrev/T
- t1/2 = 0.693/k
- t1/2 = 1/(k[A]0)
- t1/2 = [A]0/(2k)
Show Answer
Answer: t1/2 = 0.693/k
First-order half-life is independent of initial concentration.
Which option best explains first-order half-life?
- t1/2 = qrev/T
- t1/2 = [A]0/(2k)
- t1/2 = 0.693/k
- t1/2 = 1/(k[A]0)
Show Answer
Answer: t1/2 = 0.693/k
The correct concept is: t1/2 = 0.693/k. First-order half-life is independent of initial concentration.
A correct statement about first-order half-life is:
- t1/2 = qrev/T
- t1/2 = 1/(k[A]0)
- t1/2 = 0.693/k
- t1/2 = [A]0/(2k)
Show Answer
Answer: t1/2 = 0.693/k
First-order half-life is important because first-order half-life is independent of initial concentration.
What is meant by second-order half-life in physical chemistry?
- t1/2 = ΔH/T
- t1/2 = 1/(k[A]0)
- t1/2 = [A]0/(2k)
- t1/2 = 0.693/k
Show Answer
Answer: t1/2 = 1/(k[A]0)
For simple second-order reactions, half-life increases as initial concentration decreases.
Which option best explains second-order half-life?
- t1/2 = ΔH/T
- t1/2 = 1/(k[A]0)
- t1/2 = [A]0/(2k)
- t1/2 = 0.693/k
Show Answer
Answer: t1/2 = 1/(k[A]0)
The correct concept is: t1/2 = 1/(k[A]0). For simple second-order reactions, half-life increases as initial concentration decreases.
A correct statement about second-order half-life is:
- t1/2 = 0.693/k
- t1/2 = ΔH/T
- t1/2 = [A]0/(2k)
- t1/2 = 1/(k[A]0)
Show Answer
Answer: t1/2 = 1/(k[A]0)
Second-order half-life is important because for simple second-order reactions, half-life increases as initial concentration decreases.
What is meant by units of rate constant in physical chemistry?
- they depend on the overall order of reaction
- they are always mol L⁻¹ s⁻¹
- they are always dimensionless
- they depend only on the color of reactants
Show Answer
Answer: they depend on the overall order of reaction
Because rate units are concentration per time, k units change with reaction order.
Which option best explains units of rate constant?
- they are always mol L⁻¹ s⁻¹
- they depend on the overall order of reaction
- they depend only on the color of reactants
- they are always dimensionless
Show Answer
Answer: they depend on the overall order of reaction
The correct concept is: they depend on the overall order of reaction. Because rate units are concentration per time, k units change with reaction order.
A correct statement about units of rate constant is:
- they depend only on the color of reactants
- they are always dimensionless
- they are always mol L⁻¹ s⁻¹
- they depend on the overall order of reaction
Show Answer
Answer: they depend on the overall order of reaction
Units of rate constant is important because because rate units are concentration per time, k units change with reaction order.
What is meant by pseudo-first-order reaction in physical chemistry?
- a reaction with no reactants
- a zero-order reaction in every reactant
- a higher-order reaction that appears first order when one reactant is in large excess
- a reaction where equilibrium constant equals zero
Show Answer
Answer: a higher-order reaction that appears first order when one reactant is in large excess
Keeping one reactant nearly constant simplifies the observed rate law.
Which option best explains pseudo-first-order reaction?
- a higher-order reaction that appears first order when one reactant is in large excess
- a reaction with no reactants
- a zero-order reaction in every reactant
- a reaction where equilibrium constant equals zero
Show Answer
Answer: a higher-order reaction that appears first order when one reactant is in large excess
The correct concept is: a higher-order reaction that appears first order when one reactant is in large excess. Keeping one reactant nearly constant simplifies the observed rate law.
A correct statement about pseudo-first-order reaction is:
- a zero-order reaction in every reactant
- a reaction with no reactants
- a reaction where equilibrium constant equals zero
- a higher-order reaction that appears first order when one reactant is in large excess
Show Answer
Answer: a higher-order reaction that appears first order when one reactant is in large excess
Pseudo-first-order reaction is important because keeping one reactant nearly constant simplifies the observed rate law.
What is meant by initial rate method in physical chemistry?
- a method for measuring vapor pressure only
- a method used only to calculate ΔH
- a method using early reaction rates at different starting concentrations to find order
- a method that ignores concentration changes
Show Answer
Answer: a method using early reaction rates at different starting concentrations to find order
Initial rates reduce complications from reverse reactions and changing concentrations.
Which option best explains initial rate method?
- a method that ignores concentration changes
- a method for measuring vapor pressure only
- a method using early reaction rates at different starting concentrations to find order
- a method used only to calculate ΔH
Show Answer
Answer: a method using early reaction rates at different starting concentrations to find order
The correct concept is: a method using early reaction rates at different starting concentrations to find order. Initial rates reduce complications from reverse reactions and changing concentrations.
A correct statement about initial rate method is:
- a method using early reaction rates at different starting concentrations to find order
- a method used only to calculate ΔH
- a method for measuring vapor pressure only
- a method that ignores concentration changes
Show Answer
Answer: a method using early reaction rates at different starting concentrations to find order
Initial rate method is important because initial rates reduce complications from reverse reactions and changing concentrations.
What is meant by graphical method for order in physical chemistry?
- drawing molecular orbitals only
- using color names to balance equations
- plotting atomic number versus mass only
- testing linear plots of concentration functions against time
Show Answer
Answer: testing linear plots of concentration functions against time
Different reaction orders give different straight-line plots for integrated rate laws.
Which option best explains graphical method for order?
- using color names to balance equations
- plotting atomic number versus mass only
- drawing molecular orbitals only
- testing linear plots of concentration functions against time
Show Answer
Answer: testing linear plots of concentration functions against time
The correct concept is: testing linear plots of concentration functions against time. Different reaction orders give different straight-line plots for integrated rate laws.
A correct statement about graphical method for order is:
- using color names to balance equations
- testing linear plots of concentration functions against time
- drawing molecular orbitals only
- plotting atomic number versus mass only
Show Answer
Answer: testing linear plots of concentration functions against time
Graphical method for order is important because different reaction orders give different straight-line plots for integrated rate laws.
What is meant by half-life method in physical chemistry?
- a method that uses how half-life varies with initial concentration
- a method unrelated to time
- a method for naming acids
- a method that measures heat capacity only
Show Answer
Answer: a method that uses how half-life varies with initial concentration
Half-life dependence helps distinguish zero, first and second order reactions.
Which option best explains half-life method?
- a method that measures heat capacity only
- a method that uses how half-life varies with initial concentration
- a method unrelated to time
- a method for naming acids
Show Answer
Answer: a method that uses how half-life varies with initial concentration
The correct concept is: a method that uses how half-life varies with initial concentration. Half-life dependence helps distinguish zero, first and second order reactions.
A correct statement about half-life method is:
- a method that uses how half-life varies with initial concentration
- a method for naming acids
- a method unrelated to time
- a method that measures heat capacity only
Show Answer
Answer: a method that uses how half-life varies with initial concentration
Half-life method is important because half-life dependence helps distinguish zero, first and second order reactions.
What is meant by conductometric method in physical chemistry?
- following reaction progress by measuring electrical conductance
- measuring only light absorption
- measuring only mass of a solid product
- measuring only gas volume
Show Answer
Answer: following reaction progress by measuring electrical conductance
Conductance changes when ion concentrations change during a reaction.
Which option best explains conductometric method?
- measuring only gas volume
- following reaction progress by measuring electrical conductance
- measuring only mass of a solid product
- measuring only light absorption
Show Answer
Answer: following reaction progress by measuring electrical conductance
The correct concept is: following reaction progress by measuring electrical conductance. Conductance changes when ion concentrations change during a reaction.
A correct statement about conductometric method is:
- measuring only mass of a solid product
- measuring only light absorption
- following reaction progress by measuring electrical conductance
- measuring only gas volume
Show Answer
Answer: following reaction progress by measuring electrical conductance
Conductometric method is important because conductance changes when ion concentrations change during a reaction.
What is meant by spectrophotometric method in physical chemistry?
- counting crystals under a microscope only
- measuring heat capacity only
- following reaction progress by measuring absorbance
- measuring pressure only
Show Answer
Answer: following reaction progress by measuring absorbance
Absorbance changes can track colored reactants or products over time.
Which option best explains spectrophotometric method?
- measuring heat capacity only
- counting crystals under a microscope only
- measuring pressure only
- following reaction progress by measuring absorbance
Show Answer
Answer: following reaction progress by measuring absorbance
The correct concept is: following reaction progress by measuring absorbance. Absorbance changes can track colored reactants or products over time.
A correct statement about spectrophotometric method is:
- following reaction progress by measuring absorbance
- measuring pressure only
- counting crystals under a microscope only
- measuring heat capacity only
Show Answer
Answer: following reaction progress by measuring absorbance
Spectrophotometric method is important because absorbance changes can track colored reactants or products over time.
What is meant by volumetric method in physical chemistry?
- using only the final equilibrium constant
- following reaction progress by titration at selected time intervals
- measuring molecular speed directly
- using vapor pressure data only
Show Answer
Answer: following reaction progress by titration at selected time intervals
Aliquots can be withdrawn and titrated to estimate concentration over time.
Which option best explains volumetric method?
- using vapor pressure data only
- using only the final equilibrium constant
- measuring molecular speed directly
- following reaction progress by titration at selected time intervals
Show Answer
Answer: following reaction progress by titration at selected time intervals
The correct concept is: following reaction progress by titration at selected time intervals. Aliquots can be withdrawn and titrated to estimate concentration over time.
A correct statement about volumetric method is:
- using only the final equilibrium constant
- following reaction progress by titration at selected time intervals
- using vapor pressure data only
- measuring molecular speed directly
Show Answer
Answer: following reaction progress by titration at selected time intervals
Volumetric method is important because aliquots can be withdrawn and titrated to estimate concentration over time.
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