@property<EOL><INDENT>def Prl(self):<DEDENT>
Cpl, mul, kl = self.Cpl, self.mul, self.kl<EOL>if all([Cpl, mul, kl]):<EOL><INDENT>return Prandtl(Cp=Cpl, mu=mul, k=kl)<EOL><DEDENT>return None<EOL>
r'''Prandtl number of the liquid phase of the mixture if one exists at
        its current temperature and pressure, [dimensionless].

        .. math::
            Pr = \frac{C_p \mu}{k}

        Examples
        --------
        >>> Mixture(['nitrogen'], ws=[1], T=70).Prl
        2.782821450148889