@property<EOL><INDENT>def nug(self):<DEDENT>
mug, rhog = self.mug, self.rhog<EOL>if all([mug, rhog]):<EOL><INDENT>return nu_mu_converter(mu=mug, rho=rhog)<EOL><DEDENT>return None<EOL>
r'''Kinematic viscosity of the gas phase of the mixture if one exists
        at its current temperature and pressure, in units of [m^2/s].

        .. math::
            \nu = \frac{\mu}{\rho}

        Examples
        --------
        >>> Mixture(['methane'], ws=[1], T=115).nug
        2.5118460023343146e-06