For a chemical reaction, activation energy of reactants depends on ______

Answer

**Step-by-Step Solution:**

1. **Understanding Activation Energy**:
- Activation energy is defined as the minimum amount of energy that reactant molecules must possess for a reaction to occur upon collision. It is a crucial concept in chemical kinetics.

2. **Factors Affecting Activation Energy**:
- The activation energy of a reaction is influenced by several factors, but one of the primary factors is the nature of the reactants involved in the reaction.

3. **Nature of Reactants**:
- The nature of the reactants refers to their chemical and physical properties, such as whether they are ions, molecules, or gases. Different types of reactants will have different interactions and bond strengths.

4. **Ionic Reactants and Activation Energy**:
- When the reactants are ions, there is an electrostatic attraction between them. This attraction can increase the activation energy required for the reaction to occur because the ions need to overcome this attractive force to react.

5. **Bond Strengths**:
- The relative bond strengths within the reactants also play a significant role. Stronger bonds within the reactants require more energy to break, thus increasing the activation energy.

6. **Conclusion**:
- Therefore, the activation energy of reactants depends on the nature of the reactants, including their chemical structure, bond strengths, and whether they are ionic or covalent in nature.

**Final Answer**: The activation energy of reactants depends on the **nature of reactants**.

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