Magnesium oxide and nickel oxide withstand high temperatures. However, they do melt when temperature is high enough and the behaviour of mixtures of the two is of considerable interest to the ceramics industry. Draw the temperature – composition diagram for the system using the data below, where x is the mole fraction of MgO in the solid and y is its mole fraction in the liquid.
q/oC 1960 2200 2400 2600 2800
X 0 0.35 0.60 0.83 1.00
Y 0 0.18 0.38 0.65 1.00
a. temperature at which a mixture with x=0.3 begin to melt is 2167.838 celcius
b. composition liquid phase is 0.3 mol fraction, and composition solid phase is 0.7 mol fraction
c. temperature at which a liquid of composition y=0.7 will begin to solidify is 2640 celcius