Question

50.0 mL (50.0g) of water was transferred to a polystyrene calorimeter. The initial temperature was recorded as 21.6°C. Then 1.0g of ammonium nitrate weighed and transferred to the calorimeter. The mixture was stirred and the final temperature was recorded as 20.2°C.

Calculate the heat of dissolution of ammonium nitrate in kJ/mol.

Answer 1

q = [mass H2O x specific heat H2O x (Tfinal-Tinitial)] = ? in J if Cp H2O is used as 4.184 J/g*C
mols NH4NO3 = grams/molar mass = ? mols
Then heat solution is q/mol NH4NO3.
Convert to kJ/mol

Answer 2

Note: Since the temperature of the H2O cooled you know the dHsoln is + (endothermic)

Answer 3

I got 0.0037017 kj/mol. Is that correct?

Answer 4

No, Not close. Post your work if you want me to find the error.