From thermodynamics the entropy difference per unit volume between the normal and superc...

From thermodynamics the entropy difference per unit volume between the normal and superconducting states is

where B 2/2_0 is the magnetic energy density needed to return a superconductor to the normal state. Use this fact to compute the entropy difference between the normal and superconducting states in 1 mole of niobium at a temperature of 6.0 K.