Kinetics and Mechanisms: Interactive Learning Quizzes for Year 13 Chemistry

Question 1

Which of the following factors does NOT influence the rate of a chemical reaction?

Accepted Answer

Type of reaction vessel

Answer

Temperature

Answer

Concentration of reactants

Answer

Chemical structure of reactants

Question 2

Which of the following expressions represents the Arrhenius equation?

Accepted Answer

k = Ae^(-Ea/RT)

Answer

k = e^(-Ea/RT)

Answer

k = Ae^(Ea/RT)

Answer

k = RT/Ea

Question 3

Which of the following is a type of heterogeneous catalysis?

Accepted Answer

Solid catalysts

Answer

Enzymes

Answer

Liquid catalysts

Answer

Acid-base catalysis

Question 4

What is the effect of temperature on the rate of a reaction?

Accepted Answer

Increasing temperature increases the rate of reaction

Answer

Increasing temperature decreases the rate of reaction

Answer

Temperature has no effect on the rate of reaction

Answer

The effect of temperature on reaction rate depends on the specific reaction

Question 5

The half-life of a reaction represents the time required for the concentration of the reactant to decrease by what fraction?

Accepted Answer

1/2

Answer

1/3

Answer

1/4

Answer

1/5

Question 6

The rate law for a reaction is an expression that:

Accepted Answer

Relates the rate of the reaction to the concentrations of the reactants

Answer

Describes the detailed steps of the reaction mechanism

Answer

Represents the reaction order

Answer

Indicates the activation energy of the reaction

Question 7

The addition of a catalyst to a reaction:

Accepted Answer

Provides an alternative pathway for the reaction to occur with a lower activation energy

Answer

Increases the activation energy of the reaction

Answer

Decreases the rate of the reaction

Answer

Has no effect on the rate of the reaction

Question 8

Which of the following is **not** a factor that affects the rate of a chemical reaction?

Accepted Answer

Volume of the reaction vessel

Answer

Temperature

Answer

Concentration of reactants

Answer

Surface area of reactants

Question 9

The activation energy of a reaction is the minimum energy required for:

Accepted Answer

Reactants to form an activated complex

Answer

Reactants to collide

Answer

Products to form

Answer

Reaction to occur

Question 10

The half-life of a reaction is the time it takes for:

Accepted Answer

The concentration of reactants to decrease by 50%

Answer

The concentration of products to increase by 50%

Answer

The rate of the reaction to decrease by 50%

Answer

The activation energy of the reaction to decrease by 50%

Question 11

Which of the following is a characteristic of a bimolecular reaction?

Accepted Answer

It involves two molecules

Answer

Its rate law is first order

Answer

It has a low activation energy

Answer

It is often a radical reaction

Question 12

Which reaction mechanism involves the formation of a carbocation intermediate?

Accepted Answer

S<sub>N</sub>1

Answer

S<sub>N</sub>2

Answer

E1

Answer

E2

Question 13

Which of the following is a characteristic of a zeroth-order reaction?

Accepted Answer

Rate is independent of reactant concentration

Answer

Half-life is constant

Answer

Involves an intermediate

Answer

Requires a catalyst

Question 14

What is the activation energy of a reaction?

Accepted Answer

The minimum energy required for a reaction to occur.

Answer

The difference in energy between the reactants and products.

Answer

The maximum energy released by a reaction.

Question 15

Which of the following statements about catalysts is true?

Accepted Answer

Catalysts lower the activation energy of a reaction.

Answer

Catalysts are consumed in a reaction.

Answer

Catalysts increase the concentration of reactants.

Question 16

What is the half-life of a radioactive isotope?

Accepted Answer

The time it takes for half of the total radiation emitted by that isotope to decay.

Answer

The time it takes for all of an isotope to decay.

Answer

The amount of time it takes for the isotope to reach equilibrium.

Question 17

What is the relationship between the rate of a reaction and the activation energy?

Accepted Answer

The higher the activation energy, the slower the reaction rate.

Answer

The higher the activation energy, the faster the reaction rate.

Answer

The activation energy has no effect on the reaction rate.

Question 18

Which of the following is NOT a factor that influences the rate of a chemical reaction?

Accepted Answer

Type of light

Answer

Temperature

Answer

Surface area

Answer

Concentration

Question 19

The rate law for the reaction between A and B is: Rate = k[A]^2[B]. What is the order of the reaction with respect to A?

Accepted Answer

2

Answer

3

Answer

1

Question 20

Which of the following is the activation energy of a reaction?

Accepted Answer

The minimum amount of energy that must be supplied to the reactants to initiate a successful reaction.

Answer

The maximum amount of energy released by the reaction

Answer

The rate at which the reaction proceeds

Question 21

Which of the following is a catalyst?

Accepted Answer

A substance that increases the rate of a reaction without being consumed

Answer

A substance that is consumed in the reaction

Answer

A substance that decreases the rate of a reaction without being consumed

Question 22

Which of the following is a characteristic of a heterogeneous catalyst?

Accepted Answer

It is in a different physical phase from the reactants

Answer

It is consumed in the reaction

Answer

It is not affected by the surface area of the catalyst

Answer

It is in the same physical phase as the reactants

Question 23

Which of the following is NOT a factor that can influence the rate of a chemical reaction?

Accepted Answer

The color of the reactants

Answer

The presence of a catalyst

Answer

The concentration of the reactants

Answer

The temperature

Question 24

What is the best definition of activation energy?

Accepted Answer

The minimum amount of energy that reactant molecules must have to collide and react.

Answer

The energy released when a reaction occurs.

Answer

The energy difference between the reactants and products.

Question 25

How does a catalyst speed up a chemical reaction?

Accepted Answer

By providing an alternative reaction pathway with a lower activation energy.

Answer

By changing the reaction pathway.

Answer

By increasing the temperature.

Answer

By increasing the concentration of the reactants.

Question 26

Which of the following is an example of a homogeneous catalyst?

Accepted Answer

A dissolved enzyme in a solution.

Answer

Platinum used in catalytic converters.

Answer

Nickel metal used in hydrogenation.

Answer

Iron oxide used in the Haber process.

Question 27

The half-life of a reaction is the time it takes for the concentration of a reactant to:

Accepted Answer

Decrease to half its initial value.

Answer

Reach zero.

Answer

Double its initial value.

Answer

Decrease to a quarter of its initial value.

Question 28

What characterizes a first-order reaction?

Accepted Answer

The reaction rate is directly proportional to the concentration of one reactant.

Answer

The reaction rate is inversely proportional to the concentration of one reactant.

Answer

The reaction rate is directly proportional to the square of the concentration of one reactant.

Question 29

Which of the following factors does NOT directly affect the rate of a chemical reaction?

Accepted Answer

The volume of the reaction vessel (assuming constant pressure).

Answer

The concentration of reactants.

Answer

The temperature.

Answer

The presence of a catalyst.

Question 30

The rate law for the reaction 2A + B → C is found to be rate = k[A]²[B]. What is the order of the reaction with respect to A?

Accepted Answer

Second order.

Answer

Third order.

Answer

First order.

Question 31

Consider the elementary step: 2NO₂(g) → N₂O₄(g). What is the molecularity of this step?

Accepted Answer

Bimolecular.

Answer

Trimolecular.

Answer

Unimolecular.

Answer

Tetramolecular.

Question 32

The rate-determining step in a multi-step reaction is the step that...

Accepted Answer

Has the highest activation energy, thus proceeding slowest.

Answer

Is the first step in the mechanism.

Answer

Involves the highest number of molecules.

Answer

Produces the most stable product.

Question 33

A catalyst speeds up a reaction by...

Accepted Answer

Providing an alternative reaction pathway with a lower activation energy

Answer

Increasing the temperature of the reaction

Answer

Increasing the concentration of reactants

Question 34

A reaction is found to have a negative activation energy. This implies that...

Accepted Answer

The reaction is not governed by the Arrhenius equation

Answer

The reaction is exothermic

Answer

The reaction is very fast

Question 35

The half-life of a first-order reaction is...

Accepted Answer

Independent of the initial concentration of reactant

Answer

Directly proportional to the initial concentration of reactant

Answer

Inversely proportional to the initial concentration of reactant