The reaction CH₃NC(g) → CH₃CN(g) is first-order with respect to methyl isocyanide, CH₃NC. If it takes 10.3 minutes for exactly one quarter of the initial amount of methyl isocyanide to react, what is the rate constant in units of min⁻¹?

Question

Quizplus · Accepted Answer

Since the reaction is first order with respect to CH₃NC, we can use the equation: ln([CH₃NC]t/[CH₃NC]0) = -kt where [CH₃NC]t is the concentration of CH₃NC at time t, [CH₃NC]0 is the initial concentration of CH₃NC, k is the rate constant, and t is the time. If it takes 10.3 minutes for exactly one quarter of the initial amount of CH₃NC to react, that means [CH₃NC]t/[CH₃NC]0 = 0.75. Thus, we can rewrite the equation as: ln(0.75) = -k(10.3 min) Solving for k, we get: k = (ln(0.75))/(-10.3 min) = 0.0279 min ⁻¹

The Reaction CH3NC(g) → CH3CN(g) Is First-Order with Respect to Methyl

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