We interpolate data from the NIST Chemistry WebBook to characterize the density of bulk xenon gas, ρ Xe [mol/m 3 ], as a function of pressure, P , at constant temperature, T = 298 K. Fig. displays ρ Xe = ρ Xe (P ; T ). Note that 298 K is above the critical temperature of xenon (T c = 289.74 K). Near the critical pressure of xenon (P c = 58.42 bar), small changes in pressure result in large changes in density.