which has a finite jump at the critical temperature of size Δ Δ c = a 0 2 T c / b 0 . This finite jump is therefore not associated with a discontinuity that would occur if the system absorbed latent heat, since T c Δ Δ S = 0 . It is also noteworthy that the discontinuity in the specific heat is related to the discontinuity in the second derivative of the free energy, which is characteristic of a second -order phase transition. Furthermore, the fact that the specific heat has no divergence or cusp at the critical point indicates its critical exponent for c ∼ ∼ | T − − T c | − − α α is α α = 0 .