Which of the following disproportionates when treated with water ?

Options

A. `SO_(3)`
B. `F_(2)`
C. `N_(2)`
D. `Cl_(2)`

Explanation

To determine which of the given substances disproportionates when treated with water, we will analyze each option step by step.

### Step 1: Understand Disproportionation
Disproportionation is a specific type of redox reaction where a single substance is both oxidized and reduced, resulting in two different products.

### Step 2: Analyze SO3 (Sulfur Trioxide)
- When SO3 is treated with water, it reacts to form sulfuric acid (H2SO4):
\[ \text{SO}_3 + \text{H}_2\text{O} \rightarrow \text{H}_2\text{SO}_4 \]
- In this reaction, the oxidation state of sulfur remains +6 in both SO3 and H2SO4. Therefore, there is no oxidation or reduction occurring.
- **Conclusion**: SO3 does not disproportionate.

### Step 3: Analyze Fluorine (F2)
- When fluorine reacts with water, it produces hydrofluoric acid (HF) and oxygen gas (O2):
\[ 2 \text{F}_2 + 2 \text{H}_2\text{O} \rightarrow 4 \text{HF} + \text{O}_2 \]
- In this reaction, fluorine (F2) goes from an oxidation state of 0 to -1 in HF, indicating reduction. However, there is no oxidation process occurring for fluorine.
- **Conclusion**: Fluorine does not disproportionate.

### Step 4: Analyze Nitrogen (N2)
- Nitrogen is relatively inert due to its strong triple bond and does not react with water under normal conditions.
- **Conclusion**: Nitrogen does not disproportionate.

### Step 5: Analyze Chlorine (Cl2)
- When chlorine reacts with water, it undergoes disproportionation:
\[ \text{Cl}_2 + \text{H}_2\text{O} \rightarrow \text{HCl} + \text{HOCl} \]
- In this reaction, chlorine goes from an oxidation state of 0 in Cl2 to -1 in HCl (reduction) and +1 in HOCl (oxidation).
- **Conclusion**: Chlorine does disproportionate.

### Final Answer
The substance that disproportionates when treated with water is **Chlorine (Cl2)**.

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