Q57 · CSIR-NET Chemistry, June 2016
Paper: CSIR-NET June 2016 · Subject: Physical Chemistry · Chapter: Chemical Kinetics · Topic: Rate Laws Order · Marks: 2 · Difficulty: Medium
Experimentally determined rate law for the chemical reaction, \[ 2 \mathrm{NO}_{2} \mathrm{F} \rightarrow 2 \mathrm{NO}_{2}+\mathrm{F}_{2} \text { is } \mathrm{R}=\mathrm{k}\left[\mathrm{NO}_{2} \mathrm{F}\right] \]
The rate determining step consistent with the rate law is (a)$2 \mathrm{NO}_{2} \mathrm{F} \rightarrow 2 \mathrm{NO}_{2}+\mathrm{F}_{2}$
(b)$\mathrm{NO}_{2} \mathrm{F}+\mathrm{F} \rightarrow \mathrm{NO}_{2}+\mathrm{F}_{2}$
(c)$\mathrm{NO}_{2} \mathrm{F} \rightarrow \mathrm{NO}_{2}+\mathrm{F}$
(d)$\mathrm{NO}_{2}+\mathrm{F} \rightarrow \mathrm{NO}_{2} \mathrm{F}$
Answer
Answer: C ✓ checked by 4AB · confidence high
The source book printed no answer; this one was worked out and checked — see the explanation.
Explanation
A first-order rate law in NO₂F requires a unimolecular slow step: NO₂F → NO₂ + F, followed by fast F + NO₂F → NO₂ + F₂.
Study loop for Chemical Kinetics
· Browse this chapter in the app