The molecularity of an elementary reaction
`X + 2Y to `Products is

Options

A. 1
B. 2
C. 3
D. 0

Explanation

To determine the molecularity of the elementary reaction \( X + 2Y \rightarrow \text{Products} \), we can follow these steps:

### Step-by-Step Solution:

1. **Understand Molecularity**:
- Molecularity refers to the number of reactant molecules involved in an elementary reaction. It is a concept used to describe the mechanism of a reaction that occurs in a single step.

2. **Identify the Reactants**:
- In the given reaction, the reactants are \( X \) and \( Y \).

3. **Determine the Stoichiometric Coefficients**:
- The stoichiometric coefficient of \( X \) is 1 (since there is one \( X \) molecule).
- The stoichiometric coefficient of \( Y \) is 2 (since there are two \( Y \) molecules).

4. **Calculate the Total Molecularity**:
- To find the molecularity, we add the stoichiometric coefficients of all the reactants:
\[ \text{Molecularity} = \text{Coefficient of } X + \text{Coefficient of } Y = 1 + 2 = 3 \]

5. **Conclusion**:
- Therefore, the molecularity of the reaction \( X + 2Y \rightarrow \text{Products} \) is 3.

### Final Answer:
The molecularity of the elementary reaction \( X + 2Y \rightarrow \text{Products} \) is **3**.

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