The objective of this study is to investigate diffusion-thermo and radiation effects on unsteady free convection chemically reacting fluid flow past an accelerated infinite plate with variable temperature and mass diffusion under the influence of uniform transverse magnetic field when the magnetic lines of force are fixed relative to the fluid or to the plate. Two important cases, when the magnetic lines of force are being fixed relative to the fluid (K=0) or to the moving plate (K=1) have been considered. A general exact solution of the dimensionless governing partial differential equations is obtained by Laplace transform technique without any restriction. The effects of various parameters describing the flow transport in the presence of thermal radiation and Dufour effect on the fluid velocity, temperature, concentration, the rate of heat transfer and the rate of mass transfer are concentrated on through graphs. © 2018, Global Digital Central. All rights reserved.