,CHEM 104 Final Exam | Q&A | 2026/2027 | General Chemistry II |
Portage Learning
1. What is the correct definition of heat (q) in thermodynamics?
A) The transfer of mechanical energy causing matter to move against an
opposing force
B) The transfer of thermal energy between two bodies at different
temperatures
C) The energy an object possesses because of its relative position
D) The capacity to supply heat or do work
Correct Answer: The transfer of thermal energy between two bodies at
different temperatures
Rationale: Heat (q) is specifically the transfer of thermal energy between two
bodies at different temperatures. Work (w) is the transfer of mechanical
energy, potential energy is based on position, and energy is the capacity to
do work or supply heat.
2. The First Law of Thermodynamics states that:
A) Energy can be created and destroyed
B) Energy cannot be created or destroyed, only converted into other forms
C) The entropy of the universe is always increasing
D) Heat flows from cold to hot spontaneously
Correct Answer: Energy cannot be created or destroyed, only converted into
other forms
Rationale: The First Law of Thermodynamics states that energy cannot be
created or destroyed; it can only be converted from one form to another. This
is also known as the Law of Conservation of Energy.
,3. Entropy (S) is best described as:
A) The total energy of a system
B) A measure of the disorder or randomness of a system
C) The heat transferred in a reversible process
D) The capacity to do work
Correct Answer: A measure of the disorder or randomness of a system
Rationale: Entropy (S) is a thermodynamic function that measures the
disorder or randomness of a system. Higher entropy corresponds to greater
disorder.
4. The Gibbs free energy equation is:
A) ΔG = ΔH + TΔS
B) ΔG = ΔH - TΔS
C) ΔG = ΔH × TΔS
D) ΔG = ΔH / TΔS
Correct Answer: ΔG = ΔH - TΔS
Rationale: The Gibbs free energy equation is ΔG = ΔH - TΔS. This relates the
change in free energy to changes in enthalpy and entropy at a given
temperature.
5. A reaction is spontaneous when:
A) ΔG > 0
B) ΔG = 0
, C) ΔG < 0
D) ΔH > 0
Correct Answer: ΔG < 0
Rationale: A negative ΔG indicates a spontaneous reaction (exergonic). ΔG =
0 indicates equilibrium, and ΔG > 0 indicates a nonspontaneous reaction.
6. If ΔH is negative and ΔS is positive, the reaction will be:
A) Spontaneous at all temperatures
B) Nonspontaneous at all temperatures
C) Spontaneous only at low temperatures
D) Spontaneous only at high temperatures
Correct Answer: Spontaneous at all temperatures
Rationale: When ΔH < 0 (exothermic) and ΔS > 0 (increase in entropy), ΔG =
ΔH - TΔS will be negative at all temperatures, making the reaction
spontaneous at all temperatures.
7. The rate of a chemical reaction is defined as:
A) The change in concentration of reactants or products per unit time
B) The change in temperature per unit time
C) The change in pressure per unit time
D) The equilibrium constant of the reaction
Correct Answer: The change in concentration of reactants or products per
unit time
Portage Learning
1. What is the correct definition of heat (q) in thermodynamics?
A) The transfer of mechanical energy causing matter to move against an
opposing force
B) The transfer of thermal energy between two bodies at different
temperatures
C) The energy an object possesses because of its relative position
D) The capacity to supply heat or do work
Correct Answer: The transfer of thermal energy between two bodies at
different temperatures
Rationale: Heat (q) is specifically the transfer of thermal energy between two
bodies at different temperatures. Work (w) is the transfer of mechanical
energy, potential energy is based on position, and energy is the capacity to
do work or supply heat.
2. The First Law of Thermodynamics states that:
A) Energy can be created and destroyed
B) Energy cannot be created or destroyed, only converted into other forms
C) The entropy of the universe is always increasing
D) Heat flows from cold to hot spontaneously
Correct Answer: Energy cannot be created or destroyed, only converted into
other forms
Rationale: The First Law of Thermodynamics states that energy cannot be
created or destroyed; it can only be converted from one form to another. This
is also known as the Law of Conservation of Energy.
,3. Entropy (S) is best described as:
A) The total energy of a system
B) A measure of the disorder or randomness of a system
C) The heat transferred in a reversible process
D) The capacity to do work
Correct Answer: A measure of the disorder or randomness of a system
Rationale: Entropy (S) is a thermodynamic function that measures the
disorder or randomness of a system. Higher entropy corresponds to greater
disorder.
4. The Gibbs free energy equation is:
A) ΔG = ΔH + TΔS
B) ΔG = ΔH - TΔS
C) ΔG = ΔH × TΔS
D) ΔG = ΔH / TΔS
Correct Answer: ΔG = ΔH - TΔS
Rationale: The Gibbs free energy equation is ΔG = ΔH - TΔS. This relates the
change in free energy to changes in enthalpy and entropy at a given
temperature.
5. A reaction is spontaneous when:
A) ΔG > 0
B) ΔG = 0
, C) ΔG < 0
D) ΔH > 0
Correct Answer: ΔG < 0
Rationale: A negative ΔG indicates a spontaneous reaction (exergonic). ΔG =
0 indicates equilibrium, and ΔG > 0 indicates a nonspontaneous reaction.
6. If ΔH is negative and ΔS is positive, the reaction will be:
A) Spontaneous at all temperatures
B) Nonspontaneous at all temperatures
C) Spontaneous only at low temperatures
D) Spontaneous only at high temperatures
Correct Answer: Spontaneous at all temperatures
Rationale: When ΔH < 0 (exothermic) and ΔS > 0 (increase in entropy), ΔG =
ΔH - TΔS will be negative at all temperatures, making the reaction
spontaneous at all temperatures.
7. The rate of a chemical reaction is defined as:
A) The change in concentration of reactants or products per unit time
B) The change in temperature per unit time
C) The change in pressure per unit time
D) The equilibrium constant of the reaction
Correct Answer: The change in concentration of reactants or products per
unit time
