Can someone PLEASE help with this mass transfer question: as liquid flows across any plate of a distillation column its composition x, changes from the entry concentration x0,to exit x1.The composition at any point is influenced by the passage of the stripping gas at a rate G, bulk flow rate L, and the mixing on the plate by the eddy diffusivity De. If a constant Murphree point efficiency E*mv= y-y1/y*-y1 and can be assumed and a straight line equilibrium curve given by y*=mx+b show that the liquid composition satisfies the equation : De d^2x/dz^2 - V dx/dz - mGV/Lz1 E*mv (x-x*) = 0 where z is the distance measures along the plate from inlet weir, z1 is the distance between the weirs, V is linear velocity and x* is liquid composition in equilibrium...

PLEASE PLEASE HELP