Which of the following is the conjugate acid of the sulfate ion, SO_4^{2-}?

• A. HSO_4^{-}
• B. SO_3^{2-}
• C. H_2SO_4
• D. SO_4^{2-}

Answer: (A)

Verified step by step guidance

1. Recall that a conjugate acid is formed when a base gains a proton (H\^+).
2. Identify the given species: the sulfate ion is SO\_4\^{2-}, which acts as a base in this context.
3. Add one proton (H\^+) to the sulfate ion to form its conjugate acid. This means increasing the hydrogen count by one and reducing the negative charge by one.
4. Write the formula for the conjugate acid: adding H\^+ to SO\_4\^{2-} gives HSO\_4\^{-}.
5. Compare the options given and select the species that matches HSO\_4\^{-} as the conjugate acid of SO\_4\^{2-}.