Question

What are conjugate acid and base pairs? Explain with examples.

Answer 1

Conjugate acid-base pair

• Conjugate acid-base pair refers to the pair of compounds that differ by a proton.
• The pair of compounds which can mutually accept and donate hydrogen ions is called a conjugate acid-base pair.
• A proton is added to obtain the conjugate acid and a proton is removed to get the conjugate base of the compound.

Example

• ${\mathrm{HClO}}_4\rightleftharpoons {\mathrm{H}}^{+}+{{\mathrm{ClO}}_4}^{-}$
• When ${\mathrm{HClO}}_4$ donates the proton to form ${{\mathrm{ClO}}_4}^{-}$,the pair, ${{{\mathrm{HClO}}_4}^{-}\mathrm{and}{\mathrm{ClO}}_4}^{-}$acts as a conjugate base acid pair.
• $\mathrm{HCl}\rightleftharpoons {\mathrm{H}}^{+}+{\mathrm{Cl}}^{-}$
• When $\mathrm{HCl}$ donates the proton to form ${\mathrm{Cl}}^{-}$, the pair, $\mathrm{HCl}\mathrm{and}{\mathrm{Cl}}^{-}$acts as a conjugate base acid pair.