@property<EOL><INDENT>def rhos(self):<DEDENT>
Vms = self.Vms<EOL>if Vms:<EOL><INDENT>return Vm_to_rho(Vms, self.MW)<EOL><DEDENT>return None<EOL>
r'''Solid-phase mass density of the chemical at its current temperature,
        in units of [kg/m^3]. For calculation of this property at
        other temperatures, or specifying manually the method used
        to calculate it, and more - see the object oriented interface
        :obj:`thermo.volume.VolumeSolid`; each Chemical instance
        creates one to actually perform the calculations. Note that that
        interface provides output in molar units.

        Examples
        --------
        >>> Chemical('iron').rhos
        7869.999999999994