Mechanisms of mass transfer. Mass transfer by molecular diffusion: Ficks Law, diffusivity in gas, liquid, and solids, differential equations of mass transfer: steady state and transient analysis. Convective Mass Transfer. The concept of mass transfer coefficient, mass transfer coefficient for different geometries: flat plate, single sphere, cylinder, and flow in pipes. Interphases mass transfer, the two films theory. Momentum, heat and mass transfer analogy.