2. Explain how the conductivity of potassium (K), an alkali metal, with one va- lence electron per atom (and configuration (45)') is described in the nearly-free- electron model. For potassium the Hall coefficient is measured to be - 4.2x10-10 m C- and the molar volume is 46 x 10-6 m. Is the measured Hall coefficient consistent with your description? Hint: The Hall coefficient for electrons is Rh = 1e, where n is the electron density and e is the magnitude of the electronic charge