the rate constant for the decomposition of acetaldehyde, ch3cho, to methane, ch4, and carbon monoxide, co, in the gas phase is 1.10 × 10−2 m −1 s−1 at 703.7 k and 4.90 x 10-2 m−1 s−1 at 865 k. determine the activation energy for this decomposition. give your answer in kilojoules per mole and use 3 sig figs in your answer.