Chapter 16, Problem 16.91P

(a)

Interpretation Introduction

Interpretation:

Reaction energy diagram for the given mechanism has to be drawn.

Concept introduction:

Activation energy: The minimum energy required for the collision to be effective for the colliding molecules is said to be activation energy. Activation energy plays an important role in chemical kinetics. It was introduced by Swedish scientist Svante Arrhenius in 1889.

Reaction: Substances which are mutually involved each other in a chemical process and changed into different substances.

Mechanism of a reaction: The representation of step by step process involved in the chemical process is said to be mechanism of a chemical reaction.

Enthalpy: In thermodynamics, the total heat content of a system is equivalent to the thermodynamic quantity is said to be an enthalpy of a reaction.

Rate of reaction: It represents the speed at which a chemical reaction runs.  How much concentration of reactants consumed and how much concentration of product formed in a unit of time is said to be rate of reaction.

(b)

Interpretation Introduction

Interpretation:

Given alternative mechanism whether consistent with the rate law or not has to be explained.

Concept introduction:

Rate law or rate equation: The relationship between the reactant concentrations and reaction rate is expressed by an equation.

$\begin{array}{l}\text{aA + bB}\to x\text{X}\\ \\ {\text{Rate of reaction = k [A]}}^{\text{m}}{\text{[B]}}^{\text{n}}\\ \\ \text{Total}\text{order}\text{of reaction = }\left(\text{m + n}\right)\end{array}$

Order of a reaction: The order of a reaction with respect to a particular reactant is the exponent of its concentration term in the rate law expression, and the overall reaction order is the sum of the exponents on all concentration terms.

Rate constant, k: It is a proportionality constant that relates rate and concentration at a given temperature.