40 minutes = 4 half-lives. Fraction remaining = (1/2)⁴ = 1/16
Back to JEE Main 2022 Physical Chemistry
JEE Main 2022 — Chemistry Physical Chemistry
easy
mcq
2022
Official previous-year question
Verified 30 May 2026.
Question
For a first order reaction, the half-life is 10 minutes. What fraction of reactant remains after 40 minutes?
Options
- A1/2
- B1/4
- C1/8
- D1/16
Solution
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