Question

Ammonium ion is

• A. neither an acid nor base
• B. both an acid and a base
• C. a conjugate acid
• D. a conjugate base

Answer 1

Answer: (C)

a conjugate acid

Answer 2

Ammonium ion is a conjugate acid. Water behaves both as an acid as well as a base. It is amphoteric solvent. In reaction like $H _{2} O + NH _{3} \rightleftharpoons \underset{\text { conjugate acid }}{ NH _{4}^{+}}+ OH ^{-}$ it behave like an acid.