Which of the following anion behaves in a different manner than other on heating with conc. `H_(2)SO_(4)` ?

Options

A. `Cl^(-)`
B. `I^(-)`
C. `Br^(-)`
D. All behave in a similar manner

Answer

To solve the question of which anion behaves differently when heated with concentrated sulfuric acid (H₂SO₄), we will analyze the behavior of each halide ion: chloride (Cl⁻), bromide (Br⁻), and iodide (I⁻).

### Step-by-Step Solution:

1. **Identify the Anions**: The anions we are considering are chloride (Cl⁻), bromide (Br⁻), and iodide (I⁻).

2. **Reactions with Concentrated H₂SO₄**:
- **Chloride Ion (Cl⁻)**: When chloride ions react with concentrated H₂SO₄, the reaction primarily involves the transfer of protons. The reaction can be represented as:
\[ \text{Cl}^- + \text{H}_2\text{SO}_4 \rightarrow \text{HCl} + \text{HSO}_4^- \]
In this case, the chloride ion does not undergo oxidation; it acts as a proton acceptor.

- **Bromide Ion (Br⁻)**: In contrast, when bromide ions react with concentrated H₂SO₄, they can act as reducing agents. The reaction can be represented as:
\[ 2 \text{Br}^- + \text{H}_2\text{SO}_4 \rightarrow \text{Br}_2 + \text{SO}_2 + 2 \text{H}_2\text{O} \]
Here, bromide is oxidized to bromine (Br₂), and sulfuric acid is reduced.

- **Iodide Ion (I⁻)**: Similarly, iodide ions also behave as reducing agents when reacting with concentrated H₂SO₄:
\[ 8 \text{I}^- + \text{H}_2\text{SO}_4 \rightarrow 4 \text{H}_2\text{O} + \text{H}_2\text{S} + 4 \text{I}_2 \]
In this case, iodide is oxidized to iodine (I₂), and sulfuric acid is reduced to hydrogen sulfide (H₂S).

3. **Comparison of Behavior**:
- Chloride ions act as proton donors and do not undergo oxidation, while bromide and iodide ions act as reducing agents and get oxidized.
- Therefore, the behavior of chloride (Cl⁻) is distinctly different from that of bromide (Br⁻) and iodide (I⁻).

4. **Conclusion**: The anion that behaves differently when heated with concentrated H₂SO₄ is the **chloride ion (Cl⁻)**.

### Final Answer:
The chloride ion (Cl⁻) behaves differently from the bromide (Br⁻) and iodide (I⁻) ions when heated with concentrated H₂SO₄.