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

Thanks,

Michael