You may normally expect a reaction if a activation energy is required.

You may normally expect a slow reaction if a high activation energy is required.Or, You may normally expect a fast reaction if a low activation energy is required.

Explanation:

To answer this question, we should define firstly the term of activation energy.The activation energy is the minimum energy must the reacting molecules have to initiate the chemical reaction.Also, we can define it as The energy barrier that the molecules must posses an amount of energy equal or more than the value of this barrier.So, as the activation energy be of low value, the possibility that the reacting molecules can have this amount of energy to initiate and proceed the reaction increases and the reaction rate also increases.Additionally, as the activation energy be of high value, the possibility that the reacting molecules can have this amount of energy to initiate and proceed the reaction decreases and the reaction rate also decreases.

Thus, we can answer this question as:

You may normally expect a slow reaction if a high activation energy is required.You may normally expect a fast reaction if a low activation energy is required.

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