Chapter 16, Problem 16.53SP

For each of the following reactions, identify the Bronsted-Lowry acids and bases and the conjugate acid-base pairs.

1. ${\text{CN}}^{\text{-}}{\text{(aq) + H}}_{\text{2}}\text{O(l)}\rightleftharpoons {\text{OH}}^{\text{-}}\text{(aq) + HCN(aq)}$
2. ${\text{H}}_{\text{2}}{\text{PO}}_{\text{4}}{}^{\text{-}}(aq)+{\text{H}}_{\text{2}}\text{O}(l)\rightleftharpoons {\text{H}}_{\text{3}}{\text{O}}^{\text{+}}(aq){\text{ + HPO}}_{\text{4}}{}^{\text{2-}}\text{(aq)}$
3. ${\text{HPO}}_{\text{4}}{}^{\text{2-}}{\text{(aq) + H}}_{\text{2}}\text{O(l)}\rightleftharpoons {\text{OH}}^{\text{-}}{\text{(aq) + H}}_{\text{2}}{\text{PO}}_{\text{4}}{}^{\text{-}}\text{(aq)}$
4. ${\text{NH}}_{\text{4}}{}^{\text{-}}{\text{(aq) + NO}}_{\text{2}}{}^{\text{-}}\text{(aq)}\rightleftharpoons {\text{HNO}}_{\text{2}}{\text{(aq) + NH}}_{\text{3}}\text{(aq)}$