Which of the following reactions is not a disproportination reaction ?

Options

A. `NaOH+NO_(2)rarr NaNO_(2)+NaNO_(3)+H_(2)O`
B. `NaOH+Cl_(2)rarr NaCl+NaClO_(3)+H_(2)O`
C. `NaOH+S rarr Na_(2)S+Na_(2)S_(2)O_(3)+H_(2)O`
D. `NaOH+F_(2)rarr OF_(2)+NaF+H_(2)O`

Answer

To determine which of the given reactions is not a disproportionation reaction, we first need to understand what a disproportionation reaction is. A disproportionation reaction is one in which a single substance is both oxidized and reduced, resulting in products with different oxidation states.

Now, let's analyze each option step by step:

### Step 1: Analyze the first reaction (NaOH + NO2)
- **Reactants**: NO2 has nitrogen in the +4 oxidation state.
- **Products**: The products are NaNO2 (where nitrogen is +3) and NaNO3 (where nitrogen is +5).
- **Oxidation and Reduction**:
- Nitrogen in NO2 is reduced to +3 (gaining electrons).
- Nitrogen in NO2 is oxidized to +5 (losing electrons).
- **Conclusion**: This is a disproportionation reaction because nitrogen is both oxidized and reduced.

### Step 2: Analyze the second reaction (Cl2)
- **Reactants**: Cl2 has chlorine in the 0 oxidation state.
- **Products**: The products are Cl- (where chlorine is -1) and ClO3- (where chlorine is +5).
- **Oxidation and Reduction**:
- Chlorine is reduced to -1 (gaining electrons).
- Chlorine is oxidized to +5 (losing electrons).
- **Conclusion**: This is also a disproportionation reaction because chlorine is both oxidized and reduced.

### Step 3: Analyze the third reaction (S)
- **Reactants**: Elemental sulfur (S) has an oxidation state of 0.
- **Products**: The products are H2S (where sulfur is -2) and SO2 (where sulfur is +4).
- **Oxidation and Reduction**:
- Sulfur is reduced to -2 (gaining electrons).
- Sulfur is oxidized to +4 (losing electrons).
- **Conclusion**: This is a disproportionation reaction because sulfur is both oxidized and reduced.

### Step 4: Analyze the fourth reaction (F)
- **Reactants**: F2 has fluorine in the 0 oxidation state.
- **Products**: The products are both F- (where fluorine is -1).
- **Oxidation and Reduction**:
- Fluorine is reduced to -1, but there is no oxidation occurring (no increase in oxidation state).
- **Conclusion**: This is NOT a disproportionation reaction because fluorine is not undergoing both oxidation and reduction.

### Final Answer:
The reaction that is not a disproportionation reaction is the fourth one involving fluorine.

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