Question

which statement best describes the relationship between activation energy and rate of reaction? increasing the activation energy can increase the rate of a reaction. reducing the activation energy can increase the rate of a reaction. increasing the reaction energy does not alter the rate of reaction. reducing the activation energy can decrease the rate of a reaction.

Explanation:

To determine the correct statement, we recall the concept of activation energy in chemical kinetics. Activation energy is the minimum energy required for reactant molecules to undergo a reaction. A catalyst works by reducing the activation energy. When activation energy is reduced, more reactant molecules have enough energy to react, thus increasing the rate of reaction.

• The first option is incorrect because increasing activation energy would make it harder for reactants to react, decreasing the reaction rate.
• The third option is incorrect as "reaction energy" is not the same as activation energy, and changing activation energy (which is related to the energy barrier) does affect the reaction rate.
• The fourth option is incorrect because reducing activation energy should increase, not decrease, the reaction rate.
• The second option is correct because reducing the activation energy lowers the energy barrier, allowing more reactant molecules to participate in the reaction, thereby increasing the reaction rate.

Answer:

B. Reducing the activation energy can increase the rate of a reaction.