Chapter 6, Problem 6.56P

Species A is evaporating from a flat surface into species B. Assume that the concentration profile for species A in the concentration boundary layer is of the form $C_A\left(y\right)=D{y}^2+Ey+F,$ where D, E, and F are constants at any x-location and y is measured along a normal from the surface. Develop an expression for the mass transfer convection coefficient $h_m$ in terms of these constants, the concentration of A in the free stream $C_{A,\infty }$ and the mass diffusivity $D_{AB}.$ Write an expression for the molar flux of mass transfer by convection for species A.