Question

Consider this reaction: NH4+ + HPO42− → NH3 + H2PO4−

Answer 1

Bronsted Lowry Acids are donates protons
Therefor it is NH4+

Answer 2

Answer: Option (a) is the correct answer.

Explanation:

According to Bronsted-Lowry, species which are able to donate or give hydrogen ions are known as acids. Whereas species which accept hydrogen ions are known as bases.

For example, $NH^{+}_{4} + HPO^{2-}_{4} \rightarrow NH_{3} + H_{2}PO^{-}_{4}$

Here $NH^{+}_{4}$ is donating hydrogen ions hence it is the Bronsted-Lowry acid.