Calculating Heat Of Combustion

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The discussion centers around the combustion of quinone (C6H4O2) in a bomb calorimeter. The balanced equation for the complete combustion of quinone is confirmed as C6H4O2 + 6O2 → 2H2O + 6CO2. The heat of combustion calculation involves using the formula Q = CMT, where Q is the heat absorbed, C is the heat capacity of the calorimeter, M is the mass of the substance, and T is the temperature change. The calculated heat of combustion is approximately 2747 kJ/mol, which aligns closely with the textbook answer of 2740 kJ/mol. However, a potential error in the question is noted regarding the units of the calorimeter's heat capacity, suggesting it should be in kJ/K rather than kJ/M, which could affect the final calculation.
dcl
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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.

thanks in advance.
 
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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.
 
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.
 

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