Consider a reversible conversion of A to B in a stagnant liquid film at steady state. The concentrations of A and B at y=0 are CAO and CBO. The inert solid surface at y=L acts only as an impermeable barrier. The reaction kinetics is first order and reversible. The volumetric rate of reaction of A and B are RA=RB=k2CBK1CA a. Using shell balance method, develop a relation between CA and CB by solving the sum of differential component balance equations of both A and B. b. Develop the expression of CA(y)