A 1.76g sample of quinone, C6H4O2, is burned in a calorimeter whose total heat capacity is 7.854 kJ/C. The temperature of the calorimeter increases from 23.44 C to 29.14 C. What is the heat of combustion per mole of quinone? The molar mass of quinone is 108.1 g/mol.

Question

A 1.76g sample of quinone, C6H4O2, is burned in a calorimeter whose total heat capacity is 7.854 kJ/C.  The temperature of the calorimeter increases from 23.44 C to 29.14 C.  What is the heat of combustion per mole of quinone?  The molar mass of quinone is 108.1 g/mol.

The answer is -2.75x10^3 kJ/mol but I just cant quite figure out how to get that! PLEASE HELP! Thank you!

DrBob222 · Answer

0 = qcal + qcombustion 0 = Ccal*(delta T) + qcombustion 0 = 7854*delta T + qcomb Solve for qcomb Then q/mol = (qabove/1.76)*molar mass quinone