Chapter 8, Problem 8.11P

(a)

Interpretation Introduction

Interpretation:

The ${\text{K}}_{\text{b}}$ reaction for pyridine, sodium-2-mercaptoethanol, and cyanide ion has to be written.

Concept Introduction:

Base dissociation constant ${\text{K}}_{\text{b}}$:  The dissociation of weak base is given by

$\begin{array}{l}\text{B}\text{+}{\text{H}}_{\text{2}}\text{O}\rightleftharpoons {\text{BH}}^{\text{+}}\text{+}{\text{OH}}^{\text{-}}{\text{(K}}_{\text{b}}\text{reaction)}\\ \\ {\text{K}}_{\text{b}}\text{=}\frac{{\text{[BH}}^{\text{+}}{\text{][OH}}^{\text{-}}\text{]}}{\text{[B]}}\\ \\ {\text{K}}_{\text{b}}\text{is}\text{equilibrium}\text{constant}\text{called}\text{base}\text{dissociation}\text{constant}\end{array}$

(b)

Interpretation Introduction

Interpretation:

Among the pyridinium ion, 2-mercaptoethanol, and hydrogen cyanide strongest base has to be identified.