The difference of energy between activated complex and that of the reactants is called ……………… .

Answer

To solve the question regarding the difference of energy between the activated complex and that of the reactants, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Terms**:
- The activated complex is a transient state during a chemical reaction, where the reactants are in the process of being converted into products.
- The energy of the reactants is the initial energy level before the reaction starts.

2. **Energy Diagram**:
- To visualize the concept, we can draw an energy diagram. On the y-axis, we will represent energy, and on the x-axis, we will represent the progress of the reaction.
- The diagram will show the energy of the reactants at a certain level, then a peak representing the activated complex, and finally a lower energy level for the products.

3. **Identifying Activation Energy**:
- The difference in energy between the activated complex (the peak) and the energy of the reactants is defined as the activation energy (Ea).
- This is the minimum energy required for the reactants to reach the activated complex and proceed to form products.

4. **Conclusion**:
- Therefore, the difference of energy between the activated complex and that of the reactants is called **activation energy**.

### Final Answer:
The difference of energy between the activated complex and that of the reactants is called **activation energy**.

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