Assertion (A): A Chemical reaction becomes faster at higher temperatures. Reason (R): At higher temperatures, molecular motion becomes more rapid.

1. Assertion (A): A chemical reaction generally proceeds faster at higher temperatures. This is a fundamental concept in chemical kinetics. (True) 2. Reason (R): At higher temperatures, molecules possess greater kinetic energy, leading to more frequent and more energetic collisions (molecular motion becomes more rapid). A higher proportion of collisions will have energy equal to or greater than the activation energy required for the reaction to occur. (True) 3. The increased rate of effective collisions due to rapid molecular motion at higher temperatures directly explains why the reaction becomes faster. Therefore, R is the correct explanation of A.