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The rate constant of a reaction increases 4-fold when the temperature is raised from 27 deg C to 47 deg C. Calculate the activation energy (in kcal) for this reaction. (Use ln 2 = 0.7, R = 2 cal mol⁻¹ K⁻¹)
- 10 kcal
- 20 kcal
- 30 kcal
- 40 kcal
Correct answer: 10 kcal
Solution
Applying the Arrhenius equation with k2/k1 = 4 between 300 K and 320 K gives Ea about 13 kcal/mol, nearest to the 10 kcal option.
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