@property<EOL><INDENT>def rho(self):<DEDENT>
return phase_select_property(phase=self.phase, s=self.rhos, l=self.rhol, g=self.rhog)<EOL>
r'''Mass density of the mixture at its current phase and
        temperature and pressure, in units of [kg/m^3].
        Available only if single phase.

        Examples
        --------
        >>> Mixture(['decane'], ws=[1], T=550, P=2E6).rho
        498.67008448640604