Past exam of the chemistry A course of the University of Cambridge / 2024 / Paper 2 / A7 / c / iii / Solution

Using the numerical rate constants in $\mathrm{d}{\mathrm{m}}^3\mathrm{mo}{\mathrm{l}}^{-1}{\mathrm{s}}^{-1}$, the logarithms areA straight-line least-squares fit isEvery logarithmic residual has magnitude below $7.2\times 10^{-4}$, so the rates follow the fitted exponential to within $0.08\%$; $R^2\simeq 0.999997$. Thus a constant activation volume describes these data well.

Convert the slope to pascals, using $1\mathrm{atm}=101325$ Pa and $T=293.15$ K:Multiplying all rates by a common unit-conversion factor changes the intercept but leaves this slope and volume unchanged.