The motive of the paper is to study the MHD effects as well as Soret effectson unsteady MHD free convection flow of a viscous fluid past a vertical porous plate embedded with porous medium in presence of chemical reaction. In obtaining the solution, the terms concerning radiation effect, temperature gradient dependent heat source are taken into account of energy equation and chemical reaction parameter is taken into account of concentration equation. The Permeability of the porous medium and the suction velocity are considered to be as exponentially decreasing function of time. The governing...