Question
Nitric Oxide. NO reacts with oxygen to produce nitrogen dioxide.
2NO(g) + O2(g) → 2NO2(g)
The rate law for this reaction is
rate = k[NO]2 [O2]
Propose a mechanism for the above reaction.
Solution
Rate of the reaction depends upon the slowest step of the elementary processes.
Mechanism is:
NO + O2 → NO3 (fast) ...(i)
NO3 + NO → NO2 + NO2 (slow) ...(ii)
Rate law is: Rate k[NO3] [NO] but NO3 is essentially NO + O2
So, rate = k[NO]2 [O2].
