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Chemistry · 2025 · 2 marks
CBSE 2025 · Region 7 · Set 3 · Q18
Why is molecularity applicable only for elementary reactions and order is applicable for elementary as well as complex reactions?
Why is molecularity applicable only for elementary reactions and order is applicable for elementary as well as complex reactions?
Marking-scheme solution
Because molecularity of each elementary reaction in complex reaction may be different
and hence meaningless for overall complex reaction
whereas order of a complex reaction is experimentally determined by the slowest step in its
mechanism and is therefore applicable for both.
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CBSE Class 12 Chemistry past-paper question from the 2025 board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.