(3] A gas of 10% C;H, in N2 balance flows at a velocity of 0.1 m s' through a cylindrical tube(inner diameter = 8 cm) packed with porous solids (internal surface area S, = 200 m g) at 1000K and 300 kPa (isothermal and isobaric condition). The reaction, C;H, C;H, + H, is first order in C;H, that is, -r"ca = k"CHe, where k" is 8x10 m sec".When the diameter of spherical pellets is 6 mm, the resistance for internal diffusion was 5-foldhigher than that for external diffusion. (a) Calculate the overall effectiveness factor (2). (7 pt) (b) Calculate the mass transfer coefficient (k, unit =m secc"). (3 pt) (c) Calculate the exit conversion of C;H, when the reactor tube length is 3 m. (2 pt)

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