Question Detail
Question
The activation energy for the reaction CH₃CO-CH₃ + CO is 71 kJ/mol. How many times greater is the rate constant for this reaction at 170 °C than at 150 °C? R = 8.31 J/mol K.
Correct Answer
Option C is the correct answer.
Detailed Explanation
Use the two-point form of the Arrhenius equation: ln(k₂/k₁) = (Ea/R)(1/T₁ - 1/T₂). T₁ = 150 + 273 = 423 K, T₂ = 170 + 273 = 443 K. Ea = 71,000 J/mol. ln(k₂/k₁) = (71000/8.314)(1/423 - 1/443) = (8540)(0.002364 - 0.002257) = 8540 × 0.000107 = 0.914. k₂/k₁ = e⁰·⁹¹⁴ = 2.49 ≈ 2.5.
Hint
Convert temperatures to Kelvin. Use the Arrhenius equation in logarithmic form.