Question

Nitric oxide reacts with fluorine in the gas phase to form FNO(g) 2 NO(g) + F2(g) → 2 FNO(g) A kinetic study showed that the reaction mechanism consists of two elementary steps

NO + NO ⇌ N2O2 fast

N2O2 + F2 →2 FNO slow

The overall order of the reaction is therefore

A. 2

B. 2.5

C. 1

D. 3

E. 1.5

Answer 1

Answer: overall order = 3

explanation:

given reaction are-

2NO(g) + F2(g) <=======> 2FNO(g)

The reaction machanism steps are -

NO + NO <======> N2O2 (fast)

N2O2 + F2 <=======> 2FNO (slow)

We know that, for any reaction,the slow step is the rate determining step and thus, the

rate of reaction = K [N2O2]#[F2]

Since , N2O2 is present in both steps and thus it is an intermediate in the reaction, therefore, the intermediate should be replaced ,and ..for this we know that,

First step is an equillbirium because N2O2 is formed from NO and NO and thus, if Kc is equillbirium constant,

Kc =[N2O2]/[NO][NO]

Or [N2O2]=Kc[NO]^2

This will give the rate equation,

Rate of Reaction = Kc [NO2]^2[F2]

and thus , overall order of reaction = 2+1 = 3

please upvote