The first-order rearrangement of CH₃NC is measured to have a rate constant of 3.61 × 10^-15s^-1 at 298 K and a rate constant of 8.66 × 10^-7s^-1 at 425 K.Determine the activation energy for this reaction.

Question

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The activation energy can be calculated using the Arrhenius equation:k = Ae^(-Ea/RT)where k is the rate constant, A is the pre-exponential factor, Ea is the activation energy, R is the gas constant, and T is the temperature.Taking the natural logarithm of both sides of the equation, we get:ln(k) = ln(A) - (Ea/RT)Plotting ln(k) versus 1/T should give a straight line with a slope of -Ea/R.Using the given data, we can calculate the slope of the line:slope = (ln(8.66 × 10^-7) - ln(3.61 × 10^-15)) / ((1/425) - (1/298)) = -1.98 × 10^4 KTherefore, the activation energy is:Ea = -slope * R = -(-1.98 × 10^4 K) * 8.314 J/mol*K = 164 kJ/molThe closest answer choice is A) 160. kJ/mol.

The First-Order Rearrangement of CH3NC Is Measured to Have a Rate

The First-Order Rearrangement of CH₃NC Is Measured to Have a Rate