  Using the SU(3) Nambu-Jona-Lasinio (NJL) model, we study the chiral phase
transition at finite $T$ and $\mu_B$. Special attention is given to the QCD
critical end point (CEP): the study of physical quantities, as the pressure,
the entropy, the baryon number susceptibility and the specific heat near the
CEP, will provide complementary information concerning the order of the phase
transition. We also analyze the information provided by the study of the
critical exponents around the CEP.
