Which of the following best describes the difference between instantaneous and average rates?

A. Instantaneous rate is the rate at a specific time, while average rate is over an interval.

B. Instantaneous rate is the rate over an interval, while the average rate is at a specific time.

C. Both instantaneous and average rates are calculated over specific intervals.

D. Both instantaneous and average rates are calculated at specific times.

What are the units of the rate constant (k) for a second-order reaction?

A. s^(-1)

B. M^(-1) s^(-1)

C. M s^(-1)

D. No units

Which method involves plotting concentration against time to determine the order of a reaction?

A. Graphical method

B. Initial rates method

C. Half-life method

D. Steady-state approximation

What is the molecularity of an elementary step that involves a collision between two molecules?

A. Zero

B. First

C. Second

D. Third

For a zero-order reaction, how does the rate of reaction change with an increase in the concentration of the reactant?

A. Increases

B. Decreases

C. Remains constant

D. Becomes unpredictable

a) Define the term 'instantaneous rate' in the context of chemical kinetics. [2]

b) How does the instantaneous rate differ from the average rate of a reaction? [2]

a) Describe the general form of a rate law and its components. [2]

b) Explain the significance of the rate constant (K) in the rate law. [2]

a) What is meant by the term 'molecularity' in the context of reaction mechanisms? [2]

b) How does molecularity relate to the elementary steps of a reaction mechanism? [2]

a) Explain the characteristics of a zero-order reaction. [2]

b) How can the reaction order be determined using graphical methods? [3]

c) Given a straight-line graph with time on the x-axis and concentration of reactant on the y-axis for a zero-order reaction, what does the slope of the line represent? [2]

a) Describe the importance of elementary steps in understanding reaction mechanisms. [3]

b) If a reaction mechanism consists of two elementary steps, how can one determine the overall rate law? [3]

c) Define the steady-state approximation and its role in complex reactions. [2]

Which of the following is NOT a method to determine rate laws from experimental data?

A. Graphical method

B. Initial rates method

C. Steady-state approximation

D. Half-life method

In the general form of rate laws, what does the rate constant (k) represent?

A. The speed of the reaction

B. The concentration of the reactants

C. The proportionality constant relating rate to concentration

D. The order of the reaction

For which order of reaction is the half-life dependent on the initial concentration?

A. Zero-order

B. First-order

C. Second-order

D. Third-order

What does the steady-state approximation assume about the concentration of intermediates in a reaction?

A. It increases over time

B. It decreases over time

C. It remains constant over time

D. It becomes zero over time

Which of the following best describes the role of molecularity in reaction mechanisms?

A. It determines the speed of the reaction

B. It determines the order of the reaction

C. It indicates the number of molecules involved in an elementary step

D. It indicates the concentration of the reactants

a) What units would the rate constant (k) have for a second-order reaction? [2]

b) How does the rate of a reaction change if the concentration of a reactant involved in a second-order reaction is doubled? [2]

c) Describe the relationship between the rate constant (k) and temperature, referring to the Arrhenius equation. [3]

a) Differentiate between the terms 'molecularity' and 'order' in the context of reaction kinetics. [3]

b) How can the initial rates method be used to determine the order of a reaction? [3]

c) Why might the actual rate law of a reaction differ from what is expected based on its balanced chemical equation? [2]

a) Describe the concept of 'average rate' in chemical kinetics. [2]

b) Given a reaction A → B + C, if the rate law is expressed as Rate = k[A]^2, what is the order of the reaction? [1]

c) How does the rate of a reaction change if the activation energy is increased, keeping all other factors constant? [3]

d) Explain the significance of the transition state in a reaction mechanism. [2]

a) What is the role of the rate constant (k) in the rate law of a reaction? [2]

b) For a first-order reaction, describe the relationship between the half-life and the rate constant. [3]

c) Explain the concept of 'elementary steps' in a reaction mechanism. [3]

d) How does the steady-state approximation simplify the determination of rate laws for complex reactions? [2]

a) How can graphical methods be employed to determine the order of a reaction with respect to a particular reactant? [3]

b) Describe the relationship between temperature and the rate constant, as given by the Arrhenius equation. [3]

c) What is meant by the term 'molecularity' in the context of an elementary step? [2]

d) If a reaction has a high activation energy and a high frequency factor, how would this influence the rate of the reaction? [2]