(a) (5%) The velocity is constant,

(b) (8%) The experimental results show that at 200℃ the reaction is second order at low partial pressure of TTIP and zero order at high partial pressures. While at higher temperature (300 ℃ ) the reaction is second order in TTIP over the entire pressure range. Discuss these results based on the rate law derived above. [Hint: adsorption is exothermic in general]