The enthalpy of combustion of benzoic acid,C6H5COOH, which is often used to calibrate calorimeters, is
-3227kJ/mol. When 1.236g of benzoic acid was burned in a calorimeter, the tempurature increased by 2.345K. What is the specific heat of the calorimeter?
1 mole of C6H5COOH = 122.1234 g
(3227kJ/mol)/(122.1234g/mol) = 26.4241 kJ/g
Multiply that by the mass of the sample given.
Divide the answer by 2.345 C or K to get the number of kJ per degree (the calorimeter constant).
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