The reaction of NO gas with H₂ gas has the following rate law: Rate = k[H₂][NO]². A proposed mechanism is: Step 1: H₂(g) + 2NO(g) $\rightarrow$ N₂O(g) + H₂O(g)
Step 2: N₂O(g) + H₂(g) $\rightarrow$ N₂(g) + H₂O(g)
What is the molecularity of Steps 1 and 2, and which step is the slow, or rate-determining step?

Question

The reaction of NO gas with H₂ gas has the following rate law: Rate = k[H₂][NO]². A proposed mechanism is: Step 1: H₂(g) + 2NO(g)

\rightarrow

N₂O(g) + H₂O(g)
Step 2: N₂O(g) + H₂(g)

\rightarrow

N₂(g) + H₂O(g)
What is the molecularity of Steps 1 and 2, and which step is the slow, or rate-determining step?

Quizplus · Accepted Answer

Step 1 involves three molecules (H2 and 2NO), so its molecularity is 3. Step 2 involves two molecules (N2O and H2), so its molecularity is 2. The rate law matches Step 1, indicating it is the slow, rate-determining step.

The Reaction of NO Gas with H2 Gas Has the Following

The Reaction of NO Gas with H₂ Gas Has the Following