In some catalytic reactions the products adsorb more strongly than the reacting gas. This is the case, for instance, in the catalytic decomposition of ammonia on platinum at 1000 °C. As a first step in examining the kinetics of this type of process, show that the rate of ammonia decomposition should follow in the limit of very strong adsorption of hydrogen. 

Start by showing that when a gas J adsorbs very strongly, and its pressure is p_J , that the fraction of uncovered sites is approximately 1/Kp_J . Solve the rate equation for the catalytic decomposition of NH₃ on platinum and show that a plot of F(t)=(1/t) × ln(p/p₀) against G(t)=(p−p₀)/t, where p is the pressure of ammonia, should give a straight line from which k_c can be determined. Check the rate law on the basis of the following data, and find kc for the reaction.

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dpNH, dt =-k PNH, PH₂