Chapter 14, Problem 14.1QP

Consider the reaction ${\text{N}}_{\text{2}}{\text{O}}_{\text{4}}(g)\stackrel{}{\rightleftharpoons }{\text{2NO}}_{\text{2}}(g)$. Draw a graph illustrating the changes of concentrations of N₂O₄ and NO₂ as equilibrium is approached. Describe how the rates of the forward and reverse reactions change as the mixture approaches dynamic equilibrium. Why is this called a dynamic equilibrium?

Interpretation Introduction

Interpretation:

The graph representing the change in the concentrations of the reactant and product at equilibrium conditions for the given reaction has to be drawn and the term dynamic equilibrium has to be explained.

Concept introduction:

Dynamic equilibrium: When the rate of forward and reverse reactions of a chemical reaction occurs with the same rate, the system is said to be at dynamic equilibrium.

Answer to Problem 14.1QP

The graph representing the given reaction at dynamic equilibrium,

Figure 1

At dynamic equilibrium the reaction is not ceased instead both the forward and reverse reactions occurs with the same rate.

Explanation of Solution

${\text{N}}_{\text{2}}{\text{O}}_4\rightleftharpoons {\text{2NO}}_{\text{2}}$

The Graph representing the given reaction is given in figure $1$.  As the reaction proceeds, the concentration of the reactant ${\text{N}}_{\text{2}}{\text{O}}_4$ decreases and attains a constant value.  The concentration of the product ${\text{NO}}_{\text{2}}$ increases with time and attains a constant value.  At equilibrium conditions the concentrations of the reactant and the products remains constant.

Figure $1$

In a chemical reaction when the forward and the reverse reaction has the same rate the system is said to be at dynamic equilibrium.  At dynamic equilibrium the reaction is not ceased instead both the reactions occurs with the same rate.

Conclusion

The graph representing the change in the concentrations of the reactant and product at equilibrium conditions for the given reaction was drawn and the term dynamic equilibrium has been explained.