Question

Which one of the following is not acid-base conjugate pair?

• A. $ HONO,\,NO_{2}^{-} $
• B. $CH_{3}NH_{3}^{+},CH_{3}NH_{2} $
• C. $ C_6H_{5}COOH,C_{6}H_{5}COO^{-}$
• D. $ H_{3}O^{+},OH^{-} $

Answer 1

Answer: (D)

Two substance that differ from each other only by one proton are refered to as conjugate acid-base pair. except option 'c' all pairs are differ from each other only by one proton and hence they are conjugate acid-base pair. hence $H _{3} O ^{+}, OH ^{-}$are not conjugate acid-base pair.