## Vant Hoff Equation

$\Delta G^{\circ}= \Delta H^{\circ} - T \Delta S^{\circ}$

$\Delta G^{\circ}= -RT\ln K$

$\Delta G^{\circ}= \sum \Delta G_{f}^{\circ}(products) - \sum \Delta G_{f}^{\circ}(reactants)$

Posts: 21
Joined: Fri Jul 15, 2016 3:00 am

### Vant Hoff Equation

In the course reader it says that ln (K2/k1)=delta H/RT2 + delta H/Rt1 and that we can assume that delta S is constant. Why can we assume that delta S is constant?

Paul Sedaros 1B
Posts: 23
Joined: Fri Sep 25, 2015 3:00 am

### Re: Vant Hoff Equation

I think that assuming delta S is constant is what we do unless otherwise stated in a problem. The reason that I would think that we do assume delta S is constant in the Van't Hoff Equation is because it helps to eliminate the delta S/R terms in both ln K1 and ln K2 when we have ln K2/K1, making the equation easier to solve for the temperature or the K value.