Which graph shows zero activation energy ?

Options

A.
B.
C.
D.

Answer

To determine which graph shows zero activation energy, we need to understand what activation energy represents in a reaction.

### Step-by-Step Solution:

1. **Understanding Activation Energy**:
Activation energy is the minimum energy required for a chemical reaction to occur. It is represented as the energy difference between the reactants and the transition state (the highest energy point along the reaction pathway).

2. **Analyzing Graphs**:
- **Graph 1**: This graph shows a difference in energy between the reactants and the transition state. Therefore, it indicates a positive activation energy.
- **Graph 2**: Similar to Graph 1, this graph also shows a difference in energy, indicating that activation energy is present.
- **Graph 3**: This graph shows no difference in energy between the reactants and the transition state. This means that the energy level of the reactants is equal to that of the transition state, indicating zero activation energy.

3. **Conclusion**:
Based on the analysis of the graphs, **Graph 3** is the correct answer as it represents a scenario where there is zero activation energy.

### Final Answer:
**Graph 3 shows zero activation energy.**

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