A first-order reaction has a rate constant of 0.0693 per min. What is its half-life? (ln 2 = 0.693)
Answer and explanation
Correct answer: C. 10 min
- Step 1: For first order t½ = 0.693/k. Step 2. t½ = 0.693 ÷ 0.0693 = 10 min. Answer: 10 min. Why not the others: 0.1 min is what you get if you invert the formula. 14.43 min is what you get if you use 1/k. 20 min is what you get if you double the half-life.
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