Question

The conjugate acid and base of $HPO^{2-}_{4}$ respectively are

• A. $PO^{3-}_{4}$ and $H_2 PO^{-}_{4}}
• B. $H_2 PO^{-}_{4}$ and $PO^{3-}_{4}$
• C. $H_3 PO_{4}$ and $PO^{3-}_{4}$
• D. $H _2 PO _4^{-}$and $H _2 PO _4$

Answer 1

Answer: (B)

$\underset{\text{Acid}}{HPO _4^{2-}}+ H ^{+} \longrightarrow \underset{\text{Conjugate base}}{PO _4^{3-}}$ $\underset{\text{Acid}}{HPO _4^{2-}}+ H ^{+} \longrightarrow \underset{\text{Conjugate base}}{H_2PO _4^{3-}}$