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    EDIT: Sorry, title is wrong.

     kJmol^{-1} to    kJkg^{-1}

    So this is what I did to try and work this out, say for an enthalpy change of +29.3:

     \frac {kJ}{mol} \times \frac {1}{Mr} = \frac {kJ}{g}

     \frac {kJ}{g} \times \frac {1}{1000} = \frac {kJ}{kg}

    Say the molecular mass is 119.5.

    As this is how to convert the units, surely you would apply this to the enthalpy change?

     29.3 \times \frac{1}{119.5} \times \frac {1}{1000} = 2.45 \times 10^{-4}


    This clearly isn't correct, what have I done wrong?
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    (Original post by lollage123)
    EDIT: Sorry, title is wrong.

     kJmol^{-1} to    kJkg^{-1}

    So this is what I did to try and work this out, say for an enthalpy change of +29.3:

     \frac {kJ}{mol} \times \frac {1}{Mr} = \frac {kJ}{g}

     \frac {kJ}{g} \times \frac {1}{1000} = \frac {kJ}{kg}

    Say the molecular mass is 119.5.

    As this is how to convert the units, surely you would apply this to the enthalpy change?

     29.3 \times \frac{1}{119.5} \times \frac {1}{1000} = 2.45 \times 10^{-4}


    This clearly isn't correct, what have I done wrong?
    You multiply by the number of moles in a kilogram ...
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    That makes sense, K=kj/mol x mol/kg = kj/kg, but why doesn't my method work?
 
 
 
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