Chapter 16, Problem 16.42QP

Interpretation Introduction

Interpretation:

The concentrations of $H^{+},C{H}_{3}CO{O}^{-}andC{H}_{3}COOH$ in the given acetic acid solution has to be calculated.

Concept Information:

Acid ionization constant ${\text{K}}_{\text{a}}$:

Acids ionize in water.  Strong acids ionize completely whereas weak acids ionize to some limited extent.

The degree to which a weak acid ionizes depends on the concentration of the acid and the equilibrium constant for the ionization.

The ionization of a weak acid $\text{HA}$ can be given as follows,

  ${\text{HA}}_{(aq)}\to {\text{H}}^{+}{}_{(aq)}+{\text{A}}^{\text{-}}{}_{(aq)}$

The equilibrium expression for the above reaction is given below.

  $K_a=\frac{[{\text{H}}^{\text{+}}{\text{][A}}^{\text{-}}\text{]}}{[\text{HA]}}$

Where,

  $K_a$ is acid ionization constant,

  $[{\text{H}}^{\text{+}}\text{]}$  is concentration of hydrogen ion

  $[{\text{A}}^{\text{-}}\text{]}$  is concentration of acid anion

  $[\text{HA]}$ is concentration of the acid

  $\begin{array}{l}\text{Amount}\text{of}\text{substance}\left(\text{mole}\right)=\frac{\text{Given}\text{mass}}{\text{Molecular}\text{mass}}\\ \text{Concentration}=\frac{\text{Amount}\text{of}\text{substance}}{\text{Volume}\left(\text{L}\right)}\end{array}$

ICE (reaction initial concentration equilibrium) table is mainly used to calculate the value of K for a reaction. This table contains the concentration of reactant and product in various stage of reaction