Abstract
In this paper, we study the effects of Soret number and time-fractional order derivatives on the unsteady magnetohydrodynamic (MHD) natural convection heat and mass transfer flow of an incompressible viscous fluid along an infinite vertical plate with Newtonian heating and constant solute concentration embedded in a porous medium. The equations of heat and mass transfer are expressed in fractional differential equations with Caputo time-fractional derivatives. The Laplace transform method is employed to solve the energy, concentration, and momentum equations. Closed form of the temperature distribution is obtained using the Wright function, complementary error function. The species concentration and velocity field are obtained numerically by using Stehfest's algorithm. Effects of the fractional order and pertinent physical parameters on temperature, concentration, and velocity profiles are graphically presented as well.