AP Chemistryeasymcq1 pt
What is the half-life expression for a first-order reaction?
A.t½ = 0.693/k
B.t½ = [A]₀/2k
C.t½ = 1/(k[A]₀)
D.t½ = k/0.693
Explanation
Core Concept
First-order half-life depends only on k, not on initial concentration — each successive half-life takes the same time. That constancy is the diagnostic fingerprint of first order.
Correct Answer
At½ = 0.693/k
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