# Calculating Heat Of Combustion

1. Jun 14, 2004

### dcl

Hey, I need some help with the following question:

A sample of 0.1964g of Quinone (C6 H4 02, Relative Molar Mass = 108.1) was burned in a bomb calorimeter that heas a heat capacity of 1.56 kJ/M. The temperature in the caolorimeter rose from 19.3 to 22.5 degrees celcius.

(a) write a balanced equation for the complete combustion of quinone in oxygen to form water and CO2.

Ok I'm pretty sure this is right:
$$C_6 H_4 O_2 + 6O_2 \to 2H_2 O + 6CO_2$$

(b) Calculate the heat of combustion of quinone in kJ/g and kJ/mol.
Not exactly sure how to apprach this bit..

Q = CMT
where T is the difference in temp. M is the mass and C is the specific heat capcity, but I'm unsure how to apply this to the question.

2. Jun 14, 2004

### dcl

OK, think I may have worked it out..
I got an answer of around 2747 kJ/mol, whereas my book gives the answer of 2740 kJ/mol.

3. Jun 21, 2004

### Gokul43201

Staff Emeritus
This may be really late, but I hope you realize there is an error in the question, as stated by you. Heat Cap. of the calorimeter should have units of kJ/K. If this is really true, then the answer should be about 2747.6 kJ/mol as you have calculated.