Chapter 14, Problem 14.49SP

For each of the following reactions, identify the Brønsted–Lowry acids and bases and the conjugate acid–base pairs:

(a)     ${\text{CN}}^{-}\left(aq\right)+{\text{H}}_2\text{O}\left(l\right)\rightleftharpoons {\text{OH}}^{-}\left(aq\right)+\text{HCN}\left(aq\right)$

(b)     ${\text{H}}_2{\text{PO}}_4{}^{-}\left(aq\right)+{\text{H}}_2\text{O}\left(l\right)\rightleftharpoons {\text{H}}_3{\text{O}}^{+}\left(aq\right)+{\text{HPO}}_4{}^{2-}\left(aq\right)$

(c)     ${\text{HPO}}_4{}^{2-}\left(aq\right)+{\text{H}}_2\text{O}\left(l\right)\rightleftharpoons {\text{OH}}^{-}\left(aq\right)+{\text{H}}_2{\text{PO}}_4{}^{-}\left(aq\right)$

(d)     ${\text{NH}}_4{}^{-}\left(aq\right)+{\text{NO}}_2{}^{-}\left(aq\right)\rightleftharpoons {\text{HNO}}_2\left(aq\right)+{\text{NH}}_3\left(aq\right)$