Assertion: Order of a reaction is defined for both elementary as well as complex reactions.
Reason: Slowest step is the rate determining step in complex reactions.
Answer & explanation
Correct answer: option 1
Order of a reaction is defined for both elementary as well as complex reactions.
In complex (reactions occurring in more than one step) reactions, slowest step is the rate determining step because the rate of overall reaction cannot be faster than the slowest step. The molecularity of each step is unique.