The chemical reactions in which the reactants require high amount of activation energy are generally

Options

A. Slow
B. Fast
C. Instantaneous
D. Spontaneous

Answer

To solve the question regarding the nature of chemical reactions that require a high amount of activation energy, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Activation Energy**:
- Activation energy (Ea) is the minimum energy required for a chemical reaction to occur. It is the energy needed to break bonds in the reactants so that new bonds can form in the products.

2. **Analyzing the Relationship Between Activation Energy and Reaction Rate**:
- Generally, the higher the activation energy, the slower the reaction rate. This is because a higher energy barrier means that fewer molecules will have enough energy to overcome this barrier at a given temperature.

3. **Visualizing with a Reaction Coordinate Diagram**:
- If we plot a reaction coordinate diagram, the x-axis represents the progress of the reaction, while the y-axis represents the energy. The peak of the curve represents the activation energy barrier that must be overcome for the reaction to proceed.

4. **Implications of High Activation Energy**:
- When the activation energy is high, it indicates that a significant amount of energy is required to initiate the reaction. This results in a lower frequency of successful collisions between reactant molecules, leading to a slower reaction rate.

5. **Conclusion**:
- Therefore, if a chemical reaction requires a high amount of activation energy, it is generally classified as a **slow reaction**.

### Final Answer:
The chemical reactions in which the reactants require a high amount of activation energy are generally **slow**.

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