Chapter 15, Problem 1PE

(a)

Interpretation Introduction

Interpretation:

Conjugate acid-base pairs in indicated reaction have to be identified.

  ${\text{NH}}_3+{\text{H}}_{\text{2}}\text{O}\rightleftharpoons {\text{NH}}_4^{+}+{\text{OH}}^{-}$

Concept Introduction:

Bronsted-Lowry acid outlined the definition of acids that donate ${\text{H}}^{+}$ or a proton while bases that accept ${\text{H}}^{+}$ or a proton. The acidic strength is known from the ability of acid to donate ${\text{H}}^{+}$ in an aqueous solution. Explicitly the acidity strength is quantified by the magnitude of a parameter called acid ionization constant. The strong acids tend to possess higher magnitudes of acid ionization constant or $K_{\text{a}}$.

In accordance with Bronsted definition, the most usual type of acid-base reaction involves lone pair of base that reaches out for an acidic proton. Once deprotonation has occurred species assumes a negative charge and is referred to as the conjugate base of acid and other species with a positive charge as a result of proton acceptance is termed conjugate acid of given base. For example;

The strength of conjugate acid-base pairs is inversely related to each other; thus strong acid has a weak and strong base has weak conjugate counterparts and vice-versa.

(b)

Interpretation Introduction

Interpretation:

Conjugate acid-base pairs in indicated reaction have to be identified.

  ${\text{HC}}_2{\text{H}}_3{\text{O}}_{\text{2}}+{\text{H}}_{\text{2}}\text{O}\rightleftharpoons {\text{C}}_2{\text{H}}_3{\text{O}}_{\text{2}}{}^{-}+{\text{H}}_3{\text{O}}^{+}$

Concept Introduction:

Refer to part (a).

(c)

Interpretation Introduction

Interpretation:

Conjugate acid-base pairs in indicated reaction have to be identified.

  ${\text{H}}_2{\text{PO}}_4^{-}+{\text{OH}}^{-}\rightleftharpoons {\text{HPO}}_4^{2-}+{\text{H}}_2\text{O}$

Concept Introduction:

Refer to part (a).

(d)

Interpretation Introduction

Interpretation:

Conjugate acid-base pairs in indicated reaction have to be identified.

  $\text{HCl}+{\text{H}}_2\text{O}\rightleftharpoons {\text{Cl}}^{-}+{\text{H}}_3{\text{O}}^{+}$

Concept Introduction:

Refer to part (a).