## Constant

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

Jina Kwon
Posts: 100
Joined: Fri Aug 09, 2019 12:15 am

### Constant

What R constant do we use fort this equation?

Tyler Angtuaco 1G
Posts: 130
Joined: Wed Sep 11, 2019 12:16 am

### Re: Constant

I would guess the 8.314 J·K-1·mol-1 since enthalpy is in joules and temperature is in kelvin. The units would then cancel, which makes sense because the equilibrium constant has no units.

Caitlyn Tran 2E
Posts: 100
Joined: Fri Aug 09, 2019 12:15 am

### Re: Constant

The R constant depends on the units you are given and/or the units you want to end up with. For instance, if you are given volume in liters and pressure in atm, then use the constant with those units in it (8.206x10^-2). If you are calculating entropy, use the 8.314 R constant since you want entropy to be in J/K. Hope this helps!