Chapter 16, Problem 57AE

Interpretation Introduction

Interpretation:

$\text{pH}$ for ${\text{NH}}_{\text{4}}\text{Cl}$ solution has to be calculated. Also, whether ${\text{NH}}_{\text{4}}\text{Cl}$ is acidic or not has to be determined.

Concept Introduction:

For equilibrium reaction rate of forward reaction is equal to rate of reverse direction. Consider a general reaction that is as follows:

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

The expression for equilibrium constant is written as follows:

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

Here,

$K_{\text{eq}}$ is equilibrium constant

$\left[\text{A}\right]$, $\left[\text{B}\right]$, $\left[\text{C}\right]$ and $\left[\text{D}\right]$ are concentration of substances in reaction

$a$, $b$, $c$ and $d$ are coefficients of substances

$\text{pH}$ is defined as the concentration of hydrogen ion. It also explains about the acidity of solution. The $\text{pH}$ scale ranges from 0 to 14 and gives information as follows:

  $\begin{array}{l}\text{pH}<7\text{ Acidic solution}\\ \text{pH}=7\text{ Neutral}\\ \text{pH}>7\text{ Basic solution}\end{array}$