## Chemistry: The Molecular Science (5th Edition)

First pair: $HS{O_4}^-$: Base; $H_2SO_4$: Conjugate acid. Second pair: $H_2O$: Acid; $OH^-$: Conjugate acid.
As we wrote in the question above, the reaction for $HS{O_4}^-$ acting as a base is: $H{SO_4}^-(aq) + H_2O(l) \lt -- \gt H_2SO_4(aq) + OH^-(aq)$ - Identify the conjugate acid-base pairs of this reaction: 1. Identify the base and the acid in the reactants: - $HS{O_4}^-$ is turning into $H_2SO_4$; So it is gaining a proton. Therefore: $H{SO_4}^-$ is a base, and $H_2SO_4$ is its conjugate acid. - $H_2O$ is turning into $OH^-$; So it is losing a proton. Therefore: $H_2O$ is an acid, and $OH^-$ is its conjugate base.