According to collision theory, rate of the reaction increases , because

Options

A. Number of collision decreases
B. Number of molecules crossing energy barrier increases
C. Kinetic energy of molecules increases
D. Value of rate constant increases

Answer

To solve the question regarding why the rate of reaction increases according to collision theory, we can break it down into several steps:

### Step-by-Step Solution:

1. **Understanding Collision Theory**:
- Collision theory states that the rate of a chemical reaction is directly proportional to the number of collisions between reactant molecules. More collisions lead to a higher likelihood of reactions occurring.

**Hint**: Recall that collision theory emphasizes the importance of molecular interactions in chemical reactions.

2. **Effective Collisions**:
- Not all collisions result in a reaction. Only a small fraction of collisions are effective, meaning they have the proper orientation and sufficient energy to lead to a chemical reaction.

**Hint**: Consider what conditions make a collision effective versus ineffective.

3. **Activation Energy**:
- For a collision to be effective, the colliding molecules must have energy equal to or greater than the activation energy. Activation energy is the minimum energy required to initiate a chemical reaction.

**Hint**: Remember that activation energy acts as a barrier that must be overcome for a reaction to proceed.

4. **Increasing the Number of Collisions**:
- If the number of collisions between reactant molecules increases, the number of effective collisions also increases. This is because more molecules are interacting, which raises the chances of successful reactions.

**Hint**: Think about how increasing concentration or temperature can lead to more collisions.

5. **Conclusion**:
- Therefore, according to collision theory, the rate of reaction increases primarily because the number of effective collisions increases as the number of total collisions increases.

**Hint**: Summarize the relationship between collision frequency and reaction rate.

### Final Answer:
According to collision theory, the rate of the reaction increases because the number of effective collisions between reactant molecules increases, which occurs when the total number of collisions increases.