Chapter 11, Problem 97QAP

Interpretation Introduction

(a)

Interpretation:

To determine the test tube which has the smallest rate.

Concept introduction:

Rate of a chemical reaction: It tell us about the speed at which the reactants are converted into products.

Mathematically, rate of reaction is directly proportional to the product of concentration of each reactant raised to the power equal to their respective stoichiometric coefficients.

Let’s say we have a reaction:

$\begin{array}{l}\text{aA+bB}\stackrel{}{\to }\text{cC+dD}\\ \text{then,}\\ \text{rate}\text{α}{\text{[A]}}^{\text{x}}{\text{[B]}}^{\text{y}}\\ \Rightarrow \text{rate}{\text{=K}}_{\text{f}}{\text{[A]}}^{\text{x}}{\text{[B]}}^{\text{y}}\\ \text{where}{\text{K}}_{\text{f}}\text{=}\text{constant}\\ \text{x and y are order of reaction with respect to A and B }\\ \end{array}$

Interpretation Introduction

(b)

Interpretation:

To determine the change in the value of rate constant and activation energy when temperature is increased.

Concept introduction:

Relation between rate constant and temperature:

$\begin{array}{l}\text{K=}{\text{Ae}}^{\text{-}\frac{{\text{E}}_{\text{a}}}{\text{RT}}}\\ \text{where,}\\ \text{K=}\text{rate}\text{constant}\\ \text{A}\text{=}\text{Arehenius}\text{factor}\\ {\text{E}}_{\text{a}}\text{=}\text{activation}\text{energy}\\ \text{R}\text{=}\text{universal}\text{gas}\text{constant}\\ \text{T}\text{=}\text{Temperature}\end{array}$

Activation energy is the amount of energy required to reach the transition state. It is independent of temperature. Catalyst are generally added to chemical reaction to decrease activation to make reaction faster or even slower.