  We study Modified Chaplygin Gas (MCG) as a candidate for dark energy and
predict the values of parameters of the gas for a physically viable
cosmological model. The equation of state of MCG ($p=B \rho - \frac
{A}{\rho^\alpha} $) involves three parameters: $B$, $A$ and $\alpha$. The
permitted values of these parameters are determined with the help of
dimensionless age parameter ($H_{o}t_{o}$) and $H(z)-z$ Data. Specifically we
study the allowed ranges of values of B parameter in terms of $\alpha$ and
$A_{s}$ ($A_{s}$ is defined in terms of the constants in the theory). We
explore the constraints of the parameters in Cold Dark Matter(CDM) model and
UDME(Unified Dark Matter Energy) model respectively.
