`HSO_(4)^(-) + OH^(-) rarr SO_(4)^(2-) + H_(2)O` Which is correct about conjugate acid base pair

Options

A. `HSO_(4)^(-)` is conjugate acid of base `SO_(4)^(2-)`
B. `HSO_(4)^(-)` is conjugate base of acid `SO_(4)^(2-)`
C. `SO_(4)^(2-)` is conjugate acid of base `HSO_(4)^(-)`
D. None of these

Explanation

To determine the correct conjugate acid-base pairs in the reaction:

\[ \text{HSO}_4^{-} + \text{OH}^{-} \rightarrow \text{SO}_4^{2-} + \text{H}_2\text{O} \]

we need to analyze the species involved in the reaction and identify which ones act as acids and which act as bases.

### Step-by-Step Solution:

1. **Identify the Acid and Base:**
- In the given reaction, \(\text{HSO}_4^{-}\) (hydrogen sulfate ion) donates a proton (\(H^+\)) to \(\text{OH}^{-}\) (hydroxide ion).
- Since \(\text{HSO}_4^{-}\) donates a proton, it acts as an acid.
- The hydroxide ion (\(\text{OH}^{-}\)) accepts the proton, thus acting as a base.

2. **Write the Products:**
- After donating a proton, \(\text{HSO}_4^{-}\) becomes \(\text{SO}_4^{2-}\) (sulfate ion).
- The hydroxide ion (\(\text{OH}^{-}\)) that accepted the proton becomes water (\(\text{H}_2\text{O}\)).

3. **Identify Conjugate Acid-Base Pairs:**
- The conjugate base of an acid is what remains after the acid has donated a proton.
- Therefore, the conjugate base of \(\text{HSO}_4^{-}\) is \(\text{SO}_4^{2-}\).
- The conjugate acid of \(\text{OH}^{-}\) is \(\text{H}_2\text{O}\).

4. **Summarize the Conjugate Pairs:**
- Conjugate acid-base pairs:
- \(\text{HSO}_4^{-}\) (acid) and \(\text{SO}_4^{2-}\) (conjugate base)
- \(\text{OH}^{-}\) (base) and \(\text{H}_2\text{O}\) (conjugate acid)

5. **Conclusion:**
- The correct statement about the conjugate acid-base pair in the reaction is that \(\text{HSO}_4^{-}\) is the acid and \(\text{SO}_4^{2-}\) is its conjugate base.