Entropy in Van't Hoff Equation

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

Ryan Yoon 1L
Posts: 55
Joined: Mon Jul 01, 2019 12:15 am

Entropy in Van't Hoff Equation

Why is the difference in entropy the same when temperatures are increased?

christabellej 1F
Posts: 109
Joined: Sat Aug 17, 2019 12:17 am

Re: Entropy in Van't Hoff Equation

The entropy increases with temperature. In the Van't Hoff Equation though, you are using change of entropy and not entropy, and you are assuming that change of entropy is constant under temperature increase.

Joowon Seo 3A
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Joined: Sat Aug 24, 2019 12:17 am
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Re: Entropy in Van't Hoff Equation

We are assuming that both the initial and final entropy will go up the same amount so that the difference in the entropy will stay the same.

Fatemah Yacoub 1F
Posts: 114
Joined: Thu Jul 11, 2019 12:16 am

Re: Entropy in Van't Hoff Equation

The difference in entropy between reactants and products at two different temperatures is the same because despite entropy changing with temperature, you are finding the overall change in entropy, so if reactants entropy goes up then products entropy would do the opposite.