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Calculating Heat Of Combustion

  1. Jun 14, 2004 #1


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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:
    [tex]C_6 H_4 O_2 + 6O_2 \to 2H_2 O + 6CO_2 [/tex]

    (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.
  2. jcsd
  3. Jun 14, 2004 #2


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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.
  4. Jun 21, 2004 #3


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    Staff Emeritus
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    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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