AP Chemistrymediummcq1 pt
An acid-catalyzed decomposition has the slow step S + H+ -> I, where H+ is regenerated in a later step. Which rate law should experiments show?
A.rate = k[S][H+]
B.rate = k[S]
C.rate = k[I]
D.rate = k[S]^2
Explanation
Core Concept
Because this is the rate-determining elementary step, its molecularity dictates the observed law: first order in substrate and first order in the proton. A catalyst may appear in an experimental rate law even though it never appears in the overall equation. Its later regeneration restores it, allowing continuous acceleration. Acid dependence of just this form is a common experimental signature of acid catalysis.
Correct Answer
Arate = k[S][H+]
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