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heat of solution delta H solution of CaCl2 is -82.8 kJ/mol. Express answer in degrees Celsius.?

The heat of solution delta H solution of CaCl2 is -82.8 kJ/mol. Answer in degrees Celsius.? Please Help! I DO need the ANSWER BUT MORE IMPORTANT I need the STEPS to the Answer! --In the following experiment, a coffee-cup calorimeter containing 100 mL of H2O is used. The initial temperature of the calorimeter is 23*C . If 4.90 g of CaCl2 is added to the calorimeter, what will be the final temperature of the solution in the calorimeter? The heat of solution delta H solution of CaCl2 is -82.8 kJ/mol. Express answer in degrees Celsius.

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1. First you need to find out how much energy is available for this reaction: energy lost = energy gained In a calorimeter the energy is gained so J value is positive. 4.90g CaCl2(1mol/110.98) = 0.0442mol 0.0442mol)(82800J/mol) = 3656J q = mc(tf - ti) Density of H2O is 1.0 g/ml 100ml H2O(1g/ml) = 100g H2O 3656J = (100g)(4.184J/g℃)(tf - 23℃) 3656 + 9623 = 418.4tf tf = 32℃