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    To work out delta G im first carrying out a reaction to determine enthalpy change via Q=mcdeltaT.
    in the gibbs free energy equation is the temperature in kelvin equal to whatever my temperature change is in the mcdeltaT. And say if the temp change was -20 it would be 253K for the gibbs equation?
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    (Original post by User101010)
    To work out delta G im first carrying out a reaction to determine enthalpy change via Q=mcdeltaT.
    in the gibbs free energy equation is the temperature in kelvin equal to whatever my temperature change is in the mcdeltaT. And say if the temp change was -20 it would be 253K for the gibbs equation?
    Temperature change is a difference and so the units do not matter (as 1 degree celsius change = 1 Kelvin change)
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    (Original post by charco)
    Temperature change is a difference and so the units do not matter (as 1 degree celsius change = 1 Kelvin change)
    So do I use the final temperature say if went from 35 to 25 is use 298k
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    (Original post by User101010)
    So do I use the final temperature say if went from 35 to 25 is use 298k
    Q=mcΔT

    You are using the temperature change.It does not matter whether you record the values in Celsius or Kelvin.
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    If the temperature went from 10 to 25 degrees what value would I use for T in the Gibbs free energy equation
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    If temp. goes from 35 oC to 25 oC, that's a change of 35-25=10 oC.

    If temp. goes from 308 K to 298 K, that's a change of 308-298=10 K.

    They're the same thing.
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    I know they are the same but I am asking do I use the change for T in gibbs equation or what the final temp is
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    (Original post by User101010)
    I know they are the same but I am asking do I use the change for T in gibbs equation or what the final temp is
    You are clearly getting mixed up with two different issues.

    You have to work out the enthalpy change of a reaction. Do it using E=mcΔT

    Then you use your value for the enthalpy change, which does not vary with temperature (to a close approximation) with entropy values at a specific temperature (usually 298K) to find Gibbs free energy for that specified temperature.
 
 
 
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