1. Two elements A and B are mixed to form a complete solid solution at high temperatures and a miscibility gap at lower temperatures. Thermodynamic data of this system indicate that the value of WM (or as mentioned in the textbook) is 28,600 J/mol. Use Excel or MATLAB to answer the following questions:

(a) Calculate the enthalpy of mixing from XB = 0 to XB = 1 at equal intervals of 0.05 and plot the values of the enthalpy of mixing (in kJ/mole) vs. composition.

(b) Calculate the entropy of mixing at the same compositions in (a) and plot the graph of (Smix, in J/mole) vs. composition on the same plot in (a).

(c) Calculate the Gibbs energy of mixing of the same compositions at temperatures T = 900, 1000, 1100, 1200, 1300, 1400 and 1500C. Plot the Gibbs energy of mixing vs. compositions for all the above temperatures.

(d) Use the common tangent rule to construct the A-B phase diagram (T vs XB) according to the information that you obtained in (c) - Hint: fit the final data using the Polynomial fitting, order 2 (Excel).