AP Chemistryeasymcq1 pt
After three half-lives of a first-order decay, what fraction of the original reactant remains?
A.1/8
B.1/3
C.1/6
D.1/16
Explanation
Core Concept
Each half-life halves the amount: 1 → ½ → ¼ → ⅛. After n half-lives the fraction left is (½)ⁿ.
Correct Answer
A1/8
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