Which of the following statements is incorrect about the collision theory of chemicacl reaction ?

Options

A. It consider reacitng molecules or atoms to be hard spheres and ignores their structural features
B. Number of effective collisione determines the rate of reactions
C. Collision of atoms or molecules possessing sufficient threshold energy
results into the product formation.
D. Molecules should collide with sufficient threshold energy and proper
orientation for the collision to be effective.

Explanation

To determine which statement is incorrect about the collision theory of chemical reactions, we need to analyze each option based on the principles of collision theory.

### Step-by-Step Solution:

1. **Understanding Collision Theory**:
- Collision theory states that for a reaction to occur, reactant molecules must collide with sufficient energy (threshold energy) and in the correct orientation. Not all collisions lead to a reaction; only effective collisions do.

2. **Analyzing the Options**:
- **Option A**: "It considers reacting molecules of atoms to be hard spheres and ignores their structural features."
- This statement is correct. Collision theory simplifies molecules as hard spheres to focus on the energy and orientation of collisions, ignoring their complex structures.

- **Option B**: "Number of effective collisions determines the rate of reaction."
- This statement is also correct. The rate of reaction is indeed determined by the number of effective collisions, which are those that meet the energy and orientation criteria.

- **Option C**: "Collision of atoms or molecules possessing sufficient threshold energy results into the product formation."
- This statement is **incorrect** because it only mentions sufficient threshold energy. It fails to acknowledge that proper orientation is also necessary for effective collisions to lead to product formation. Thus, this statement is incomplete.

- **Option D**: "Molecules should collide with sufficient threshold energy and proper orientation for the collision to be effective."
- This statement is correct as it includes both necessary conditions for effective collisions: sufficient energy and proper orientation.

3. **Conclusion**:
- After analyzing all the options, **Option C** is the incorrect statement regarding the collision theory of chemical reactions because it omits the importance of proper orientation in addition to threshold energy.

### Final Answer:
The incorrect statement about the collision theory of chemical reactions is **Option C**.

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