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    Can anybody help me to underatand a question on molar enthalpy change please?
    Basically, the question is about an experiment to investigate the strength of intermolecular forces between ethyl ethanoate molecules and trichloromethane molecules. 0.10mol of each liquid is mixed in a copper calorimeter (starting temp for both is the same).
    Results found are:
    Mass of ethyl ethanoate = 8.80g
    " " of throchloromethane = 11.95g
    Temp. Increase on mixing = 9.5K.

    The question asks me to calculate heat required to increase the temperature of each liquid by 9.5K during mixing (which I've done), but then asks me to use those answers to calculate molar enthalpy change in kJ mol-¹ for the mixing process, which is the part I dont understand. How do I do this? I have the equation of ∆H = -q/n but I'm not sure what each bit of this represents, or how to use it. Help would be much appreciated, sorry it's such a long question!
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    (Original post by KLouise99)
    Can anybody help me to underatand a question on molar enthalpy change please?
    Basically, the question is about an experiment to investigate the strength of intermolecular forces between ethyl ethanoate molecules and trichloromethane molecules. 0.10mol of each liquid is mixed in a copper calorimeter (starting temp for both is the same).
    Results found are:
    Mass of ethyl ethanoate = 8.80g
    " " of throchloromethane = 11.95g
    Temp. Increase on mixing = 9.5K.

    The question asks me to calculate heat required to increase the temperature of each liquid by 9.5K during mixing (which I've done), but then asks me to use those answers to calculate molar enthalpy change in kJ mol-¹ for the mixing process, which is the part I dont understand. How do I do this? I have the equation of ∆H = -q/n but I'm not sure what each bit of this represents, or how to use it. Help would be much appreciated, sorry it's such a long question!
    Imagine that you mix one mole of each together. The energy released is your enthalpy change.

    However, you can't work this out without the specific heat capacities of the two liquids
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    (Original post by charco)
    Imagine that you mix one mole of each together. The energy released is your enthalpy change.

    However, you can't work this out without the specific heat capacities of the two liquids
    The question does give me the specific heat capacities, I just didnt include them in this post I dont understand what calculation I need to do though?
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    (Original post by KLouise99)
    The question does give me the specific heat capacities, I just didnt include them in this post I dont understand what calculation I need to do though?
    If you have calculated the energy change for 0.1 mol of liquid (for example) then you multiply it by 10 to get per mole.

    Basically divide the energy change by the number of moles that you have used.
 
 
 
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