Question

Consider the mechanism. Step 1: 2 A ⟶ B + C slow Step 2: B + C ⟶ E fast Overall: 2 A ⟶ E Determine the rate law for the overall reaction, where the overall rate constant is represented as k .

Answer 1

Answer:

rate = k[A]²

Explanation:

Two principles:

• The steps in a mechanism are elementary reactions, so the exponents in the rate laws are the coefficients in the steps.
• No reaction can go faster than its slowest step.

Step 1: 2A ⟶ B + C (slow)  

Step 2: B + C ⟶ E (fast)  

Overall: 2A ⟶ E

The rate law for the reaction is the same as that for Step 1:

rate = k[A]²