Hosten and Froment (Ghent) studied the isomerization of n-pentane to i-pentane in the presence of hydrogen over a bifunctional Pt-Al,O, catalyst. Globally, first a dehydrogenation takes place over the metallic function, followed by an isomer- ization over the acidic alumina sites, and finally a hydrogenation of the i-pentene takes place over Pt. The reaction sequences can be given as Dehydrogenation 1 A +* + A* 2 A* + * + M* + H,* 3 H,* + H, + 4 M* ++ M+* Isomerization 1 M+# + M# 18 5 Chemical Kinetics of Catalyzed Reactions 2 M# 3 N# N# + N+# Hydrogenation 1 N+* + N* 2 H, +* + H,* 3 N* + H,* + B* +* 4 B + B+* a) Derive a rate expression for this reaction where step 6 is rate determining. All other steps can be considered in quasi-equilibrium, and the quasi-steady-state approximation is valid. b) The overall reaction rate is found to be independent of the total pressure. Is that in agreement with your result?