CHEM 130 Test 3 Questions and
Answers 2025/2026.
Which set of results applies to a reaction that is not spontaneous at 273 K but is spontaneous at
400 K? - Answer If the reaction is spontaneous at high temperatures and nonspontaneous at
low temperatures, this indicates that both the ∆H and ∆S are greater than 0.
Is a positive ΔG value spontaneous or nonspontaneous? - Answer nonspontaneous
∆H° - Answer ΔHo=Σ productsnΔHof(products)−ΣreactantsnΔHof(reactants)
ΔSo - Answer ΔSo=Σ productsnSof(products)−ΣreactantsnSof(reactants)
free energy is positive - Answer nonspontaneous
free energy is negative - Answer spontaneous
free energy is 0 - Answer reaction is neither spontaneous nor nonspontaneous
potential energy - Answer stored energy
kinetic energy - Answer energy of motion
work - Answer energy required to move matter against an opposing force
heat - Answer The energy transferred between objects that are at different temperatures
enthalpy - Answer the heat content of a system
system - Answer set of substances/energy that is being studied
, open system - Answer A system in which matter can enter from or escape to the
surroundings.
isolated system - Answer a system in which neither energy nor matter can enter or leave the
system
exothermic - Answer Releases heat
endothermic - Answer Absorbs heat
heat capacity - Answer the amount of heat needed to increase the temperature of an object
exactly 1°C
specific heat - Answer The amount of energy required to raise the temperature of 1 gram of
a substance by 1 degree celcius
heating curve - Answer a plot of temperature versus time for a substance where energy is
added at a constant rate
heat of fusion - Answer the energy a substance must absorb in order to change from a solid
to a liquid
heat of vaporization - Answer The amount of energy required for the liquid at its boiling
point to become a gas
calorimetry - Answer The precise measurement of heat flow out of a system for chemical
and physical processes
Hess's Law - Answer the overall enthalpy change in a reaction is equal to the sum of enthalpy
changes for the individual steps in the process
State function - Answer A function that depends only on the initial and final states of a
system, not on the path in between.
Answers 2025/2026.
Which set of results applies to a reaction that is not spontaneous at 273 K but is spontaneous at
400 K? - Answer If the reaction is spontaneous at high temperatures and nonspontaneous at
low temperatures, this indicates that both the ∆H and ∆S are greater than 0.
Is a positive ΔG value spontaneous or nonspontaneous? - Answer nonspontaneous
∆H° - Answer ΔHo=Σ productsnΔHof(products)−ΣreactantsnΔHof(reactants)
ΔSo - Answer ΔSo=Σ productsnSof(products)−ΣreactantsnSof(reactants)
free energy is positive - Answer nonspontaneous
free energy is negative - Answer spontaneous
free energy is 0 - Answer reaction is neither spontaneous nor nonspontaneous
potential energy - Answer stored energy
kinetic energy - Answer energy of motion
work - Answer energy required to move matter against an opposing force
heat - Answer The energy transferred between objects that are at different temperatures
enthalpy - Answer the heat content of a system
system - Answer set of substances/energy that is being studied
, open system - Answer A system in which matter can enter from or escape to the
surroundings.
isolated system - Answer a system in which neither energy nor matter can enter or leave the
system
exothermic - Answer Releases heat
endothermic - Answer Absorbs heat
heat capacity - Answer the amount of heat needed to increase the temperature of an object
exactly 1°C
specific heat - Answer The amount of energy required to raise the temperature of 1 gram of
a substance by 1 degree celcius
heating curve - Answer a plot of temperature versus time for a substance where energy is
added at a constant rate
heat of fusion - Answer the energy a substance must absorb in order to change from a solid
to a liquid
heat of vaporization - Answer The amount of energy required for the liquid at its boiling
point to become a gas
calorimetry - Answer The precise measurement of heat flow out of a system for chemical
and physical processes
Hess's Law - Answer the overall enthalpy change in a reaction is equal to the sum of enthalpy
changes for the individual steps in the process
State function - Answer A function that depends only on the initial and final states of a
system, not on the path in between.
