Question

In the presence of a catalyst, which statement accurately describes the reaction rate?

a) It decreases
b) It increases
c) It remains the same
d) It becomes zero

Answer 1

The reaction rate increases with the presence of a catalyst because it provides an alternative pathway with a lower activation energy, leading to more effective collisions and a faster reaction. The correct answer is b) It increases.

Step-by-step explanation:

In the presence of a catalyst, the reaction rate increases. A catalyst provides an alternative reaction pathway with a lower activation energy compared to the uncatalyzed reaction. This means that more reactant molecules have the required energy to reach the transition state and form products. Therefore, the addition of a catalyst increases the number of effective collisions per unit time, thus increasing the overall reaction rate.

Examples of Catalysts in Chemical Reactions

For example, in the Haber process for synthesizing ammonia, a catalyst made of iron mixed with K2O and Al2O3 is used to increase the reaction rate. Similarly, enzymes act as biological catalysts that increase the rate of biochemical reactions.