Question

step 1: 2 no₂(g) → no₃(g) + no (g) (slow)
step 2: no₃(g) + co(g) → no₂(g) + co₂(g) (fast)
a proposed two - step mechanism for the chemical reaction no₂(g) + co(g) → no(g) + co₂(g) is shown above. which of the following equations is a correct rate law that is consistent with the elementary steps in the mechanism?
a rate = kno₂
b rate = kno₂²
c rate = kno₃co
d rate = kno₂co

Explanation:

Step1: Identify rate-determining step

The slow step (Step 1: \( 2\text{NO}_2(g)
ightarrow \text{NO}_3(g) + \text{NO}(g) \)) determines the reaction rate.

Step2: Derive rate law for slow step

For an elementary reaction, the rate law is based on reactant stoichiometry. Here, 2 moles of \(\text{NO}_2\) react, so rate \(= k[\text{NO}_2]^2\).

Answer:

B. \(\text{Rate} = k[\text{NO}_2]^2\)