The rate constant, kkk, for the thermal decomposition of ethanal was measured at several temperatures. A graph of ln(k)\ln(k)ln(k) against 1T\displaystyle \frac{1}{T}T1 (where T T\,T is the temperature in K\text{K}K) was plotted, and the line of best fit had a gradient of -2.23 × 104 K.
What is the activation energy, EaE_{\text{a}}Ea, for this reaction in kJ mol−1\text{kJ mol}^{-1}kJ mol−1?
(Use the gas constant, R=8.314 J K−1 mol−1R = 8.314\text{ J K}^{-1}\text{ mol}^{-1}R=8.314 J K−1 mol−1)
+2.68+2.68+2.68
+18.5+18.5+18.5
+185+185+185
+1.85×105+1.85 \times 10^5+1.85×105