Question: In the following experiment, a coffee-cup calorimeter containing 100. mL of H2O is used. The initial temperature of the calorimeter is 23.0 ∘C. If 8.50 g of CaCl2 is added to the calorimeter, what will be the final temperature of the solution in the calorimeter? The heat of solution, ΔHsoln, of CaCl2 is −82.8 kJ/mol. The specific heat of water is Cs =4.184 J/(g−K)

After going through the problem my self I've ended up with 38.16 ∘C but apparently it's wrong I'm not sure what could be the problem because I feel like calculated everything correctly