Question

The solid in question 2 was aluminum sulfate, al2(so4)3. calculate the molar heat of solution, δhsoln, for aluminum sulfate. hint: the units for molar heat of solution are kilojoules per mole (kj/mole). first determine the heat released per gram of solid.

Answer 1

The solution for this problem is:

The information given lacks but nevertheless the answer is:
So, the total heat free by dissolving the solute was 1386 + 32 = 1417 J
Then, dissolving of the solute will have released -1417 J. So, per gram of Al2 (SO4)3 dissolved: 
-1417 J / 25 g = -56.7 J/g 

Translating that to a per mole: -56.7 J/g X 342 g/mol = -1.94X10^4 J/mol = -19 kJ/mol = this would be Delta Hsoln