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For a reversible reaction, if the activation energy of the forward process is 50 kcal, what can be said about the activation energy of the reverse process?

1. It is less than 50 kcal
2. It may be either greater than or less than 50 kcal
3. It is exactly 50 kcal
4. It is greater than 50 kcal

Correct answer: It may be either greater than or less than 50 kcal

Solution

The activation energy of the reverse process can vary depending on the energy difference between the reactants and products; thus, it can be either greater than or less than the activation energy of the forward process.

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