CHEM 104 - Module 2: Chemical Kinetics 2026/2027 UPDATE
1. What branch of chemistry specifically studies the speeds or rates of chemical
reactions?
A. Thermodynamics
B. Electrochemistry
C. Chemical Kinetics
D. Quantum Mechanics
Answer: C
Rationale: Chemical kinetics is the study of reaction rates, the factors that affect them, and
the molecular mechanisms by which reactions occur.
2. Which of the following units is typically used to express the rate of a
reaction?
A. M·s
B. M/s
C. s/M
D. 1/M
Answer: B
Rationale: Reaction rate is the change in concentration (Molarity) over a change in time
(seconds), resulting in units of M/s.
,3. In the reaction A + B -> C, if the concentration of A is doubled and the rate
quadruples, what is the order with respect to A?
A. Zero order
B. First order
C. Third order
D. Second order
Answer: D
Rationale: If doubling the concentration causes the rate to increase by 2 squared (4), the
reaction is second order with respect to that reactant.
4. What is the unit of the rate constant (k) for a first-order reaction?
A. 1/s
B. M/s
C. 1/(M·s)
D. 1/(M^2·s)
Answer: A
Rationale: For a first-order reaction, Rate = k[A]. Since Rate is M/s and [A] is M, k must
have units of 1/s to balance the equation.
5. Which factor generally increases the rate of a chemical reaction by increasing
the frequency and energy of collisions?
A. Increasing the temperature
B. Decreasing the temperature
C. Increasing the volume of the container
D. Decreasing the surface area
Answer: A
Rationale: Increasing temperature increases the kinetic energy of particles, leading to
more frequent and more energetic collisions.
, 6. What is the ‘overall order’ of a reaction with the rate law: Rate = k[A][B]^2?
A. 1
B. 3
C. 2
D. 0
Answer: B
Rationale: The overall order is the sum of the individual exponents in the rate law: 1 + 2 =
3.
7. For a zero-order reaction, how does the rate change as the concentration of
the reactant decreases?
A. The rate decreases linearly
B. The rate remains constant
C. The rate decreases exponentially
D. The rate increases
Answer: B
Rationale: In a zero-order reaction, the rate is independent of the concentration of the
reactant.
8. A plot of ln[A] versus time yields a straight line for which order of reaction?
A. First order
B. Zero order
C. Second order
D. Third order
Answer: A
Rationale: The integrated rate law for a first-order reaction is ln[A] = -kt + ln[A]0, which
fits the linear equation y = mx + b.
1. What branch of chemistry specifically studies the speeds or rates of chemical
reactions?
A. Thermodynamics
B. Electrochemistry
C. Chemical Kinetics
D. Quantum Mechanics
Answer: C
Rationale: Chemical kinetics is the study of reaction rates, the factors that affect them, and
the molecular mechanisms by which reactions occur.
2. Which of the following units is typically used to express the rate of a
reaction?
A. M·s
B. M/s
C. s/M
D. 1/M
Answer: B
Rationale: Reaction rate is the change in concentration (Molarity) over a change in time
(seconds), resulting in units of M/s.
,3. In the reaction A + B -> C, if the concentration of A is doubled and the rate
quadruples, what is the order with respect to A?
A. Zero order
B. First order
C. Third order
D. Second order
Answer: D
Rationale: If doubling the concentration causes the rate to increase by 2 squared (4), the
reaction is second order with respect to that reactant.
4. What is the unit of the rate constant (k) for a first-order reaction?
A. 1/s
B. M/s
C. 1/(M·s)
D. 1/(M^2·s)
Answer: A
Rationale: For a first-order reaction, Rate = k[A]. Since Rate is M/s and [A] is M, k must
have units of 1/s to balance the equation.
5. Which factor generally increases the rate of a chemical reaction by increasing
the frequency and energy of collisions?
A. Increasing the temperature
B. Decreasing the temperature
C. Increasing the volume of the container
D. Decreasing the surface area
Answer: A
Rationale: Increasing temperature increases the kinetic energy of particles, leading to
more frequent and more energetic collisions.
, 6. What is the ‘overall order’ of a reaction with the rate law: Rate = k[A][B]^2?
A. 1
B. 3
C. 2
D. 0
Answer: B
Rationale: The overall order is the sum of the individual exponents in the rate law: 1 + 2 =
3.
7. For a zero-order reaction, how does the rate change as the concentration of
the reactant decreases?
A. The rate decreases linearly
B. The rate remains constant
C. The rate decreases exponentially
D. The rate increases
Answer: B
Rationale: In a zero-order reaction, the rate is independent of the concentration of the
reactant.
8. A plot of ln[A] versus time yields a straight line for which order of reaction?
A. First order
B. Zero order
C. Second order
D. Third order
Answer: A
Rationale: The integrated rate law for a first-order reaction is ln[A] = -kt + ln[A]0, which
fits the linear equation y = mx + b.
