Chapter 16, Problem 16.117QP

Interpretation Introduction

Interpretation:

The amount of methyl amine in 100 mL of solution has to be calculated.

Concept Introduction:

Basic nature of amines: Amines react with aqueous mineral acids to from ammonium salts. Amines are basic in nature as the lone pair of electrons on nitrogen can be donated.

  $R-N{H}_2+H-X\underset{}{\overset{}{\rightleftarrows }}R-N{H}_3^{+}{X}^{-}$

Base ionization constant $K_b$

The equilibrium expression for the ionization of weak base $\text{B}$ will be,

  ${\text{B}}_{(aq)}+{\text{H}}_{\text{2}}{\text{O}}_{(l)}\stackrel{}{\to }{\text{HB}}^{\text{+}}{}_{(aq)}+{\text{OH}}^{\text{-}}{}_{(aq)}$

  ${\text{K}}_b=\frac{[{\text{HB}}^{\text{+}}][{\text{OH}}^{\text{-}}]}{[\text{B}]}$

Where $K_b$ is base ionization constant, $[{\text{OH}}^{-}\text{]}$ is concentration of hydroxide ion, $[{\text{HB}}^{\text{+}}\text{]}$ is concentration of conjugate acid, $[\text{B]}$ is concentration of the base