Chemical Forums
Chemistry Forums for Students => Physical Chemistry Forum => Topic started by: Knockabout on August 21, 2007, 06:02:08 AM
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Hi, I'm in the middle of determining ∆G° using the Van't Hoff equation on data from a differential scanning calorimeter. DNA denaturation was measured.
The values are calculated following our course manual, however, I'd like to better understand some of the assumptions taken during these calculations.
1) ∆H° and ∆S° are independent of temperature (or at least in the interval of interest here, I guess).
-This assumption must be based on ∆Cp = 0.. Is that an okay assumption?
2) ∆H = ∆H° (the measured enthalpy - from the DSC - equals the standard enthalpy).
-I asked my supervisor about this one, and got the answer that, "because my solutions is very diluted it's okay".. What's the reasoning behind this?
I hope somebody can help, any ideas are much appreciated ;D
Thanks,
Michael