Question

H_2S+SO_4^2−⇌ ______ ⇌ HS ^− +HSO_4^−

Which of the above chemical species is the Brønsted-Lowry acid?

A. HS^−
B. H_2​
C. SO_4^2−
D. HSO_4^−

Answer 1

The Brønsted-Lowry acid in the reaction is HSO4− (Option D), as it can donate a proton to another species, for example, water, forming the sulfate ion (SO4−2) and hydronium ion (H3O+).

Step-by-step explanation:

In the reaction sequence provided, the species that functions as a Brønsted-Lowry acid is D. HSO4−. This ion can donate a proton (H+) to another species, thereby acting as an acid. For example, HSO4− can donate a proton to water to form H3O+ and the sulfate ion (SO4−2), according to the following net ionic equation:

HSO4−(aq) + H2O(l) → SO4−2(aq) + H3O+(aq)

Therefore, the answer to the question is D. HSO4−, as it is the species that can donate a proton, becoming the sulfate ion (SO4−2) which is its conjugate base.