Which factor effects the rate of a reaction but is not consumed during the course of the reaction?

The correct answer is a catalyst.

Explanation:

Catalysts are substances that can be added to a reaction to increase the reaction rate without being consumed in the process.

They generally work by reducing the energy of the transition state and thus decreasing the activation energy or changing the mechanism of the reaction. This also changes the nature (and energy) of the transition state. Biochemical processes, such as glucose oxidation, rely heavily on enzymes, proteins that act as catalysts.

Other common types of catalysts are acid-base catalysts and heterogeneous or surface catalysts.

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