16-09U

The weakly nonequilibrium heat-conduction steady state of a low-density gas is considered in the approximation of the linear temperature profile. Simple analytical estimates for pressure, internal energy, and entropy are obtained. Compressibilities and heat capacities are analyzed. The result for the entropy is shown to be compatible with the second law of thermodynamics. The approximation of the displaced linear temperature profile is introduced, which is aimed to take into account nonlinearity of the true temperature profile.