The present paper deals with thermal radiation effects on the transient hydro-magnetic natural convection ow past a vertical plate embedded in a porous medium with mass discussion and fluctuating temperature about time at the plate, by taking account the heat due to viscous dissipation in the presence of chemical reaction. The governing equations are solved numerically by Ritz finite element method. The effects of various parameters entered into the equations of momentum, energy and concentration are evaluated numerically and plotted graphically, while numerical values of variations in skin-friction, rate of heat transfer in terms of Nusselt number at the plate are presented in tabular form. The results of the study are discussed