Dissociation of a gas caused by a temperature gradient, a dissociating gas (for example, Na₂ → 2Na) is enclosed in a tube, sealed at both ends, and the two ends are maintained at different temperatures. Because of the temperature gradient established, there will be a continuous flow of Na₂ molecules from the cold end to the hot end, where they dissociate into Na atoms, which in turn flow from the hot end to the cold end. Set up the equations to find the concentration profiles. Check your results against those of Dirac.