`NO+NO_(2) overset(-11^(@)C) to N_(2)O_(3)`

Options

A. For disproportionation reaction.
B. For comproportionation reaction.
C. For either intermolecular redox reaction or displacement reaction
D. For either thermal combination redox reaction or thermal decomposition redox reaction.

Answer

To determine the type of reaction for the equation \( \text{NO} + \text{NO}_2 \overset{-11^\circ C}{\rightarrow} \text{N}_2\text{O}_3 \), we will analyze the oxidation states of nitrogen in the reactants and products.

### Step-by-Step Solution:

1. **Identify the Reactants and Products**:
- Reactants: Nitric oxide (NO) and nitrogen dioxide (NO₂)
- Product: Dinitrogen trioxide (N₂O₃)

2. **Determine the Oxidation States**:
- For NO:
- The oxidation state of nitrogen (N) in NO can be calculated as follows:
\[ \text{Oxidation state of N} = x + (-2) = 0 \quad \Rightarrow \quad x = +2 \]
- For NO₂:
- The oxidation state of nitrogen (N) in NO₂:
\[ \text{Oxidation state of N} = x + 2(-2) = 0 \quad \Rightarrow \quad x = +4 \]
- For N₂O₃:
- The oxidation state of nitrogen (N) can be calculated as:
\[ 2x + 3(-2) = 0 \quad \Rightarrow \quad 2x - 6 = 0 \quad \Rightarrow \quad 2x = 6 \quad \Rightarrow \quad x = +3 \]

3. **Analyze the Changes in Oxidation States**:
- In the reaction:
- One nitrogen atom goes from +2 (in NO) to +3 (in N₂O₃).
- Another nitrogen atom goes from +4 (in NO₂) to +3 (in N₂O₃).
- This indicates that nitrogen is being both oxidized (from +2 to +3) and reduced (from +4 to +3).

4. **Classify the Reaction**:
- Since a single element (nitrogen) is present in two different oxidation states in the reactants and is converted to a product with a single oxidation state, this reaction is classified as a **comproportionation reaction**.
- Additionally, since two reactants combine to form one product, it is also a **combination reaction**.

5. **Determine the Nature of the Reaction**:
- The reaction occurs at a low temperature (-11°C), which suggests that it is likely to be **exothermic** because the formation of a stable product (N₂O₃) from less stable reactants (NO and NO₂) releases energy.

### Conclusion:
The reaction \( \text{NO} + \text{NO}_2 \rightarrow \text{N}_2\text{O}_3 \) is a **comproportionation reaction** and a **combination reaction**. It is also **exothermic**.