Given is the mechanism of decomposition of N2O5.(i) N2O5 → NO2 + NO3(ii) NO2 + NO3 → NO + NO2 + O2(iii) NO + NO3 → 2 NO2The order of reaction is:
Correct answer: A. 1
- A. 1
- B. 2
- C. 3
- D. 0
Explanation
The decomposition of N2O5 is described by a three-step mechanism. The first step, N2O5 → NO2 + NO3, is the slowest and thus the rate-determining step. This means the overall reaction rate is dependent on the concentration of N2O5 alone, making the reaction first order. The other steps occur more quickly and do not affect the overall rate. Options B, C, and D are incorrect because they suggest reaction orders inconsistent with the given mechanism.
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