Collision theory is applicable to

Options

A. Uniniolecular reactions
B. Bimolecular reactions
C. Trimolecular reactions
D. Tetra molecular reactions

Answer

### Step-by-Step Solution:

1. **Understanding Collision Theory**:
Collision theory is a model that explains how chemical reactions occur and why reaction rates differ for different reactions. It states that for a reaction to occur, reactant molecules must collide with sufficient energy and proper orientation.

2. **Requirements for Collision**:
- **Effective Collisions**: Not all collisions lead to a reaction. Only effective collisions, where molecules collide with enough energy and the correct orientation, result in the formation of products.
- **Geometry**: The orientation of the colliding molecules is crucial. If the molecules do not align properly, even if they collide, they may not react.

3. **Types of Reactions**:
- **Unimolecular Reactions**: These involve a single reactant molecule undergoing a change. Collision theory is not applicable here since there is no collision between two molecules.
- **Bimolecular Reactions**: These involve two reactant molecules colliding. Collision theory is applicable here because the reaction depends on the collision between these two molecules.

4. **Conclusion**:
Based on the principles of collision theory, it is clear that it is applicable to bimolecular reactions. The correct answer to the question is that collision theory is applicable to bimolecular reactions.

### Final Answer:
Collision theory is applicable to bimolecular reactions.

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