AP Chemistryeasymcq1 pt
In a two-step mechanism, the first step is slow and the second is fast. What determines the observed rate law?
A.The first step
B.The second step
C.The average of both steps
D.The step with more reactants
Explanation
Core Concept
The slow step is the bottleneck — the rate-determining step. Its molecularity sets the rate law, with fast steps treated as following instantly behind.
Correct Answer
AThe first step
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