Question

Identify the Br??sted acid in the following equation: $PO _{4}^{3-}+ H _{2} O (l) \longrightarrow HPO _{4}^{2-}(a q)+ OH ^{-}(a q)$

• A. $OH^{-}$
• B. $PO^{3-}_4$
• C. $HPO_4$
• D. $H_2 O$

Answer 1

Answer: (D)

$H_2 O$

Answer 2

In the reaction :

$PO _{4}^{3-}+ H _{2} O (l) \longrightarrow HPO _{4}^{2-}(a q)+ OH ^{-}(a q)$

Only $H _{2}$ O acts as Bronsted acid among the given options as it donate the proton $\left( H ^{+}\right)$ to give $OH ^{-}$ ions.