Temperature { Consider the Cu-Ag phase diagram. 1000 800 Composition (at % Ag) 20 40 60...

   

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Temperature { Consider the Cu-Ag phase diagram. 1000 800 Composition (at % Ag) 20 40 60 80 100 2000 Liquidus Solidus Liquid a + L B 780C (TE) 7.9 (CF) 600 Solvus + B 1800 F 1600 E A+L 71.9 91.2 1400 (C) (CB) B 1200 1000 H 800 400 20 40 60 80 100 (Cu) Composition (wt % Ag) (Ag) Temperature (F) When T = 1000 F (~550 C) and the average composition of Ag is 71.9 weight percent, fill in the answers on the table on the next page. Show how you determined your answers by marking the figure above. (a) What is the melting temperature? (1 point) Answer (a): What is the composition (b) of Ag in the alpha phase? (c) Answer (b): in the beta phase? (2 points each) Answer (c): Using the lever rule, calculate (d) the fraction of atoms (in Answer (d): terms of weight % is fine) in the alpha phase and (e) the fraction of atoms in the beta phase. (4 points each) Answer (e): Answer (f): (f) Is the enthalpy of mixing positive, negative or zero for this system? (2 point) (g) What is the entropy of mixing in the alpha phase and (h) Answer (g): beta phase? (4 points each) (i) What is the total entropy of mixing in the system? (1 points) Answer (h): Answer (i): Temperature { Consider the Cu-Ag phase diagram. 1000 800 Composition (at % Ag) 20 40 60 80 100 2000 Liquidus Solidus Liquid a + L B 780C (TE) 7.9 (CF) 600 Solvus + B 1800 F 1600 E A+L 71.9 91.2 1400 (C) (CB) B 1200 1000 H 800 400 20 40 60 80 100 (Cu) Composition (wt % Ag) (Ag) Temperature (F) When T = 1000 F (~550 C) and the average composition of Ag is 71.9 weight percent, fill in the answers on the table on the next page. Show how you determined your answers by marking the figure above. (a) What is the melting temperature? (1 point) Answer (a): What is the composition (b) of Ag in the alpha phase? (c) Answer (b): in the beta phase? (2 points each) Answer (c): Using the lever rule, calculate (d) the fraction of atoms (in Answer (d): terms of weight % is fine) in the alpha phase and (e) the fraction of atoms in the beta phase. (4 points each) Answer (e): Answer (f): (f) Is the enthalpy of mixing positive, negative or zero for this system? (2 point) (g) What is the entropy of mixing in the alpha phase and (h) Answer (g): beta phase? (4 points each) (i) What is the total entropy of mixing in the system? (1 points) Answer (h): Answer (i):