What ions hydrolyze in aqueous solutions?
Hydrolysis of an ion is its reaction with water to produce an acidic or basic solution.
(1) Sodium acetate is a salt of the weak acid acetic acid. Acetate ion is the conjugate base of acetic acid. It hydrolyzes in water to form a basic solution:
CH₃COO⁻(aq) + H₂O(l) ⇌ CH₃COOH(aq) + OH⁻(aq)
Ammonium chloride is a salt of the weak base ammonia. Ammonium ion is the conjugate acid of the weak base ammonia. It hydrolyzes in water to form an acidic solution:
NH₄⁺(aq) + H₂O(l) ⇌ NH₃(aq) + H₃O⁺(aq)
(2) Metal ions are Lewis acids. In solution, they form aqua ions with the general formula