Question 2

Nitrous acid ($HNO_2$) is unstable and undergoes disproportionation at room temperature in aqueous solution according to the following reaction: $3HNO_2(aq) \rightarrow HNO_3(aq) + 2NO(g) + H_2O(l)$ In an aqueous environment, nitric acid ($HNO_3$) fully dissociates into hydronium and nitrate ions: $HNO_3(aq) + H_2O(l) \rightarrow H_3O^+(aq) + NO_3^-(aq)$ Thus, the final species present in the solution are $H_3O^+$, $NO_3^-$, and $NO$ gas.