1. Two moles of solid Cr2O3 at 2500K are dissolved in a large volume of liquid Raoultian solution of Al2O3 and Cr2O3 in which xCr2O3=0.2 (mole fraction does not change after the addition of Cr2O3 ) and which is also at 2500K. At the melting temperature of Cr2O3,2538K, the change of molar entropy due to melting is Sm,Cr2O3=46.25J/K. Calculate the changes in enthalpy and entropy caused by the addition of Cr2O3 at 2500K under the following two conditions a). cp(Cr2O3 liquid )cp(Cr2O3 solid )=0; b )cp(Cr2O3 liquid )cp(Cr2O3 solid )=10J/ K. (Hint: for Raoultian solution, mixing itself does not lead to a change of enthalpy. The enthalpy comes from the melting of solid Cr2O3 at 2500K.)