Question

The decomposition of hydrogen peroxide (H2O2(aq)) is proposed to follow a reaction mechanism of: Step 1: H2O2(aq) + Br–(aq)→H2O(l) + BrO–(aq) Step 2: BrO–(aq) + H2O2(aq)→H2O(l) + O2(g) + Br–(aq) What is the catalyst, and what is the effect of having a catalyst present? Question 15 options: 1) Br– is the catalyst, and the reaction follows a faster pathway with Br– than without. 2) BrO– is the catalyst, and the reaction follows a faster pathway with BrO– than without. 3) Br– is the catalyst, and the reaction follows a slower pathway with Br– than without. 4) BrO– is the catalyst, and the reaction follows a slower pathway with BrO– than without.

Answer 1

Option (1) Br– is the catalyst, and the reaction follows a faster pathway with Br– than without

Step-by-step explanation:

Let us consider the equation below:

Step 1:

H2O2(aq) + Br–(aq) → H2O(l) + BrO–(aq)

Step 2:

BrO–(aq) + H2O2(aq) → H2O(l) + O2(g) + Br–(aq)

From the above equation, we can see that Br– is unchanged.

This implies that Br– is the catalyst as catalyst does not take part in a chemical reaction but they create an alternate pathway to lower the activation energy in order for the reaction to proceed at a much faster rate to arrive at the products.