Question

How does a catalyst speed up chemical reactions?

Answer 1

Catalysts can speed chemical reactions by lowering the activation energy 

Answer 2

Answer:

By lowering down the activation energy.

Explanation:

Activation energy is the energy required to transform the substrate into the high energy state that is eventually converted into the product. High energy requirement in the form of activation energy does not allow the reactions to occur at a higher rate under room temperature.  

Catalysts are the substances that speed up the chemical reaction by lowering down the activation energy. The reduced energy requirement allows the reactions to occur at higher rates in presence of catalysts.