Which ion is hydrogen sulfate?

Which ion is hydrogen sulfate?

• A. HSO3-
• B. H2SO4
• C. HSO4-
• D. SO4^2-

Answer: (C)

Hydrogen sulfate is the anion HSO4−. It forms when sulfuric acid loses one proton, so sulfuric acid is diprotic: its first dissociation gives HSO4− and H+, and the second dissociation gives SO4^2− and H+. That makes HSO4− the singly protonated, or bisulfate, form of sulfate. The other options are a neutral molecule (H2SO4), the doubly negatively charged ion (SO4^2−), and a different ion (hydrogen sulfite, HSO3−). So the ion that corresponds to hydrogen sulfate is HSO4−.

Hydrogen sulfate is the anion HSO4−. It forms when sulfuric acid loses one proton, so sulfuric acid is diprotic: its first dissociation gives HSO4− and H+, and the second dissociation gives SO4^2− and H+. That makes HSO4− the singly protonated, or bisulfate, form of sulfate. The other options are a neutral molecule (H2SO4), the doubly negatively charged ion (SO4^2−), and a different ion (hydrogen sulfite, HSO3−). So the ion that corresponds to hydrogen sulfate is HSO4−.