Question

Conjugate base of $H_{2}P{O}_4^{-}$ is:

• A. $HP{O}_4^{2-}$
• B. $P{O}_4^{3-}$
• C. $H_{3}P{O}_4$
• D. $HP{O}_4^{-}$

Answer 1

The correct option is A $HP{O}_4^{2-}$

According to the Bronsted-Lowry, a conjugate acid-base pair consists of two substances that differ only by the presence of a proton $H^{+}$. A conjugate acid is formed when a proton is added to a base, and a conjugate base is formed when a proton is removed from an acid.
$H_{2}P{O}_4^{-}\to \underset{\text{(Conjugate base)}}{HP{O}_4^{2-}}+H^{+}$