Gas A is diffusing from a turbulent stream across a stagnant film up to a catalyst surface where the following reaction occurs; 2AB, at point 1 in the stagnant film (zl). Species B then diffuses back to the turbulent gas stream opposite to the diffusion of A. At point 2 in the film (z2), the partial pressure of A is pA2=0.1atm. a) Derive the expression for NA at constant pressure P (1 atm) and steady state for an instantaneous reaction at the catalyst surface. b) For DAB=0.2104m2/s,T=298K and film thickness of 1mm, determine the flux of A,NA