Q. Which of the following is not a conjugate acid base pair?
A) $HPO_{3}^{2 -},\ PO_{3}^{3 -}$
B) $H_{2}PO_{4}^{-},\ HPO_{4}^{2 -}$
C) $H_{3}PO_{4},\ H_{2}PO_{4}^{-}$
D) $H_{2}PO_{4}^{-},\ PO_{3}^{3 -}$
Explanation
(d)
$Acid_{1} + Base_{2} \rightleftharpoons Acid_{2} + Base_{1}$
$HPO_{3}^{2 -} + H_{2}O \rightleftharpoons H_{3}O^{+} + PO_{3}^{3 -}$
$H_{2}PO_{4}^{-} + H_{2}O \rightleftharpoons H_{3}O^{+} + HPO_{4}^{2 -}$
$H_{3}PO_{4} + H_{2}O \rightleftharpoons H_{3}O^{+} + H_{2}PO_{4}^{-}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.