Consider a liquid mixture, $20$ mole $\%$ of component $($a$)$ and $80$ mole $\%$ of component $($b$)$ at $328K,$ as shown below. Lewis$-$Randall reference state and the two$-$suffix Margules equation are applied.

Determine the followings;

the two$-$suffix Margules equation parameters.

the fugacity of component $($a$)$ in the liquid.

the fugacity of component $($b$)$ in the vapor.

the mole fraction of component $($b$)$ in the vapor.

solve the question by using azeotroph approach.