© Kwok-Wai Ng, 1998.

4. Free electron gas (a) Show that the kinetic energy of a free electron gas at absolute zero is where is the Fermi energy. (b) Derive expressions for the pressure and the bulk modulus . (c) Estimate the contribution of the conduction electrons to B for potassium and compare your answer to the experimentally measured bulk modulus . Potassium has a bcc structure of lattice parameter 5.225.