  Solar models through evolutionary phases of gravitational contraction,
pre-main sequence and MS phases, up to current age 4.5E9 yr. and 4.57E9 yr.,
were studied adopting different prescriptions for the equation of state (EOS)
and different opacity tables. The results are compared with solar models we
computed with different radiative opacities (Cox & Stewart 1970) and different
EOS, as with models computed by other authors. Finally we provide the internal
run of the thermodynamic quantities of our preferred solar model which
possesses the following characteristics: age 4.50E9 yr., initial He abundance
by mass 0.285, parameter of the mixing length alpha=1.82, radius and
temperature at the bottom of the convective envelope are R(bottom)=0.724 Rsun
and T(bottom)=2.14E6 K, respectively.
