## Van't Hoff Eq.

$\ln K = -\frac{\Delta H^{\circ}}{RT} + \frac{\Delta S^{\circ}}{R}$

Tschlener 1E
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Joined: Mon Jan 26, 2015 2:17 pm

### Van't Hoff Eq.

In our course reader we see that the Van't Hoff eq is: lnk=(-deltaH/RT)+(delta S superscript 0/R)

But then further down the page it say the eq is : ln(k1/k2)= (-deltaH superscript 0/R)[1/T2-1/T1]

I know that these would be used in different instances, but my question is which equation is the formal Van't Hoff eq.? Like if a problem said to use the Van't Hoff equation, which one would we try to derive first?

thanks!

Chem_Mod
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### Re: Van't Hoff Eq.

The first equation is the Vant Hoff's equation. The second is nothing but an extension of the original equation. Depending on what you are supposed to find in the question, you should use the suitable equation

Noelle Min-1N
Posts: 10
Joined: Wed Sep 21, 2016 2:58 pm

### Re: Van't Hoff Eq.

To get the Van't Hoff equation, why is the ln(K1-K2) equation multiplied by -1 on both sides to make it into ln (K2-K1)?