The molecularity of a complex reaction given below is :
`2N_(2)O_(5)(g)to4NO_(2)(g)+O_(2)(g)`

Options

A. 1
B. 2
C. 3
D. no meaning

Answer

To determine the molecularity of the given reaction, we need to understand the concept of molecularity and its applicability to the reaction provided.

### Step-by-Step Solution:

1. **Identify the Reaction**: The reaction given is:
\[ 2N_{2}O_{5}(g) \rightarrow 4NO_{2}(g) + O_{2}(g) \]

2. **Understand Molecularity**: Molecularity refers to the number of reactant molecules involved in an elementary reaction. It is defined only for elementary reactions, which are single-step reactions that occur in one stage.

3. **Determine the Type of Reaction**: The reaction provided is a complex reaction, which means it involves multiple steps or is not a simple elementary reaction.

4. **Conclusion on Molecularity**: Since molecularity is not defined for complex reactions, we conclude that the molecularity of the given reaction is **not defined**.

### Final Answer:
The molecularity of the reaction \(2N_{2}O_{5}(g) \rightarrow 4NO_{2}(g) + O_{2}(g)\) is **not defined**.

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