Question

Whether the conjugate base of ${\mathrm{NH}}_3$ is ${{\mathrm{NH}}_3}^{+}$ or not. Explain why?

Answer 1

The conjugate base of ${\mathrm{NH}}_3$:

• A conjugate base is the outcome of a chemical process where an acid contributes to a proton.
• As a consequence, a conjugate base is a species synthesized by eliminating a proton from acid, although it can acquire a hydrogen ion in the reverse reaction.
• Furthermore, a conjugate base is a species synthesized when a proton is eliminated from acid, as it can gain a hydrogen ion in the reverse process.

$$\begin{gathered} \mathrm{Acid}+\mathrm{base}\rightleftharpoons \mathrm{conjugate}\mathrm{acid}+\mathrm{conjugate}\mathrm{base} \\ -\mathrm{Conjugate}\mathrm{acid}\mathrm{of}{\mathrm{NH}}_3\mathrm{is}{{\mathrm{NH}}_4}^{+}. \\ \mathrm{When}{\mathrm{NH}}_3\mathrm{takes}\mathrm{up}\mathrm{a}\mathrm{proton},\mathrm{it}\mathrm{gets}\mathrm{converted}\mathrm{to}\mathrm{its}\mathrm{conjugate}\mathrm{acid}. \\ -\mathrm{Conjugate}\mathrm{base}\mathrm{of}{\mathrm{NH}}_3\mathrm{is}{{\mathrm{NH}}_2}^{-}. \\ \mathrm{When}{\mathrm{NH}}_3\mathrm{releases}\mathrm{a}\mathrm{proton}\mathrm{it}\mathrm{gets}\mathrm{converted}\mathrm{to}\mathrm{its}\mathrm{conjugate}\mathrm{base}. \end{gathered}$$

• We could, however, look for a different solvent. Ammonia goes through a process that can be easily condensed in a laboratory.
• $2{\mathrm{NH}}_3\rightleftharpoons {{\mathrm{NH}}_4}^{+}+{{\mathrm{NH}}_2}^{-}$
  As a consequence, the conjugate acid of ammonia is ammonium ion ${{\mathrm{NH}}_4}^{+}$ although the conjugate base is an amide ion ${{\mathrm{NH}}_2}^{-}$.