  We study the chiral phase transition at finite temperature $T$ and baryonic
chemical potential $\mu_B$ within the framework of the SU(3) Nambu-Jona-Lasinio
(NJL) model. The QCD critical end point (CEP) and the critical line at finite
$T$ and $\mu_B$ are investigated: the study of physical quantities, such as the
baryon number susceptibility and the specific heat in the vicinity the CEP,
will provide relevant information concerning the order of the phase transition.
The class of the CEP is determined by calculating the critical exponents of
those quantities.
