Chapter 14, Problem 14.1QE

Interpretation Introduction

Interpretation:

The condition that explains whether the system is in equilibrium or not has to be explained.

Concept Introduction:

The equilibrium state of a reaction is generally studied by equilibrium constant. It is the ratio of the concentration of products by concentration of reactants at equilibrium. The general equilibrium reaction is as follows:

  $a\text{A}+b\text{B}\rightleftharpoons c\text{C}+d\text{D}$

Here,

$\text{A}$ and $\text{B}$ are the reactants.

$\text{C}$ and $\text{D}$ are products.

$a$ and $b$ are the stoichiometric coefficients of reactants.

$c$ and $d$ are the stoichiometric coefficients of products.

The expression of the equilibrium constant for the above reaction is as follows:

  $K_{\text{c}}=\frac{{\left[\text{C}\right]}^c{\left[\text{D}\right]}^d}{{\left[\text{A}\right]}^a{\left[\text{B}\right]}^b}$

Here,

$K_{\text{c}}$ is the equilibrium constant.

$\left[\text{C}\right]$ is the concentration of $\text{C}$.

$\left[\text{D}\right]$ is the concentration of $\text{D}$.

$\left[\text{A}\right]$ is the concentration of $\text{A}$.

$\left[\text{B}\right]$ is the concentration of $\text{B}$.

Explanation of Solution

To examine whether the system is in equilibrium or not the equilibrium condition must be satisfied. The condition of equilibrium is a state of balance of processes that runs in opposite directions. At equilibrium, the formation of product from reactant balances the formation of reactant from the product. Also, the change in concentration of reaction and product seems to be negligible at equilibrium state.