You are dealing with a binary liquid  solution of species (1) and (2) at 1 bar. The molar Gibbs energy for this  liquid solution is given as

 g=1000x₁+800x₂+RT(x₁lnx₁+x₂lnx₂)+6000x₁x₂  [J/mol]

(1) Identify the terms in the g-x₁-x₂ expression provided.  Based on this expression, describe the nature of interactions for this binary  system. Determine the constant for the two-suffix Margules model.

(2)  Explain why partial miscibility can be developed for this binary  solution. Use the fugacity criteria to determine the equilibrium compositions  of two partially miscible phases at a given temperature (T); that is to derive  the expressions for the pair of co-existing partially miscible  solutions. Present and explain your process clearly.