Chapter 18.3, Problem 29LC

Interpretation Introduction

Interpretation: The explanation for how a balanced chemical equation is used to write an equilibrium constant expression is to be stated.

Concept Introduction: The reaction in which the rate of the forward reaction is equal to the rate of the backward reaction is called an equilibrium reaction.

Answer to Problem 29LC

The balanced chemical equation for the reaction is used for writing the powers of the reactant and product in the expression of equilibrium constant thus, in this way a balanced chemical equation is used to write an equilibrium constant expression.

Explanation of Solution

The ratio of the concentration of the products to the concentration of the reactants raised to some power is termed an equilibrium constant.

For example, taking a reaction for the formation of dinitrogen tetroxide via a reaction of two molecules of nitrogen oxide. The chemical equation for the same is given as;

  $\text{2NO}\left(g\right)\rightleftharpoons {\text{N}}_2{\text{O}}_4\left(g\right)$

Now, the equilibrium constant expression for the above reaction is given as;

  ${\text{K}}_{\text{eq}}=\frac{\left[{\text{N}}_{\text{2}}{\text{O}}_{\text{4}}\right]}{{\left[\text{NO}\right]}^2}$

The balanced chemical equation for the reaction is used for writing the powers of the reactant and product in the expression of equilibrium constant thus, in this way a balanced chemical equation is used to write an equilibrium constant expression.