Consider the dissolution of CaCl2.
A 10.6-g sample of CaCl2 is dissolved in 109 g of water, with both substances at 25.0°C. Calculate the final temperature of the solution assuming no heat lost to the surroundings and assuming the solution has a specific heat capacity of 4.18 J/°C · g.
The Attempt at a Solution
I had thought Q=ΔH = -81.5kJ = -81.5 x 10^3 J
the mass would be 10.6+109 g
and since the solution overall has a heat capacity of 4.18 J/°Cg, I plugged the numbers in:
81.5 x 10^3 = (10.6+109)x4.18x(T_f-25)
Then I got T_f = 188 °C, which is wrong, but I don't understand why. I don't have much time until the assignment is due, so could someone please help me out? Thank you!