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    Trying to revise for a chem exam soon and came across this question.

    How would you go about doing this calculation...

    0.16g of methanol is used up when a spirit burner heats 100g of water from 17 to 24 degrees. Calculate the enthalpy change of combustion of methanol.

    Thank you very much!
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     E_h = cm \Delta T
    Put in mass of water (in kg) and specific heat capacity of water and the change in temperature.
    Work out the no. of moles of methanol and divide heat by no. of moles
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    (Original post by soup)
     E_h = cm \Delta T
    Put in mass of water (in kg) and specific heat capacity of water and the change in temperature.
    Work out the no. of moles of methanol and divide heat by no. of moles
    sorry, why do you have to do this bit "Work out the no. of moles of methanol and divide heat by no. of moles " ??
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    (Original post by me_myself_and_I)
    sorry, why do you have to do this bit "Work out the no. of moles of methanol and divide heat by no. of moles " ??
    That's how you calculate the enthalpy of combustion of methanol. If you don't divide by the no. of moles then the "enthalpy" will change. It's a constant.
 
 
 
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