Why are reactions of higher order less in number?

Explanation

### Step-by-Step Text Solution:

1. **Understanding Collision Theory**:
- The first step in answering the question is to understand the collision theory of chemical reactions. According to this theory, a chemical reaction occurs when reactant molecules collide with sufficient energy and proper orientation.

2. **Probability of Collision**:
- The likelihood of a reaction occurring is directly related to the probability of collisions between reactant molecules. In lower-order reactions (first and second order), the number of molecules involved in the reaction is fewer, which increases the chances of collisions.

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