Chapter 18, Problem 18.185P

(a)

Interpretation Introduction

Interpretation:

Fraction of $\text{HClO}$ at pH 7.00 has to be calculated.

Concept Introduction:

Dissociation of $\text{HClO}$ can be written as follows,

$HClO+H_{2}O\stackrel{}{\rightleftarrows }{H}_3{O}^{+}+Cl{O}^{-}$

So, acid dissociation constant for the above equation is given below.

$K_a=\frac{\left[H_3{O}^{+}\right]\left[Cl{O}^{-}\right]}{\left[HClO\right]}$

$pH$ of the solution can be calculated from the following equation.

$pH=-{\log }_{}[H_3{O}^{+}]$

 Or $[H_3{O}^{+}]$ can be calculated using same relation if $pH$ is known.

(b)

Interpretation Introduction

Interpretation:

Fraction of $\text{HClO}$ at pH 10.00 has to be calculated.

Concept Introduction:

Dissociation of $\text{HClO}$  can be written as follows,

$HClO+H_{2}O\stackrel{}{\rightleftarrows }{H}_3{O}^{+}+Cl{O}^{-}$

So, acid dissociation constant for the above equation is given below.

$K_a=\frac{\left[H_3{O}^{+}\right]\left[Cl{O}^{-}\right]}{\left[HClO\right]}$

$pH$ of the solution can be calculated from the following equation.

$pH=-{\log }_{10}[H_3{O}^{+}]$

Or $[H_3{O}^{+}]$ can be calculated using same relation if $pH$ is known.