Same chapter3 marksDifficulty: Medium
For a first-order reaction, 50% of the reactant is used up in 10 minutes. What fraction remains after 30 minutes?
Chemical Kinetics
3 marksDifficulty: Medium
The half-life of a first-order reaction is 20 minutes. Calculate its rate constant.
Original Khojo Papers practice question — not from a past board paper.
Answer
About 0.0347 min−1
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
For a first-order reaction t½ = 0.693/k, so k = 0.693 ÷ 20 = 0.0347 min−1.
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Solutions