Question

The mechanism of the following reaction is:

2NO (g) + 2H₂ (g) ¾® N₂ (g) + 2H₂O(g)

Step1 : 2NO (g) + H₂ (g) $\xrightarrow { \text { slow } }$ N₂ + H₂O₂

Step2 : H₂O₂ + H₂$\xrightarrow { \text { fast } }$2H₂O

• A. Rate = k [NO]² [H₂]²
• B. Rate = k [H₂O₂] [H₂]
• C. On doubling the concentration of H₂, keeping the concentration of NO constant, the rate will become double
• D. If the initial concentration of H₂ and NO is C_o and after time "t" the concentration of N₂ is x then Rate = k (C_o – 2x)²

Answer 1

Answer: (C)

On doubling the concentration of H₂, keeping the

concentration of NO constant, the rate will become double

Answer 2

r.d.s. is step 1.

r = k [NO]² [H₂]

\ On doubling the concentration of H₂ without changing the concentration of NO, the rate will become double.