## Residual Entropy

Volume: $\Delta S = nR\ln \frac{V_{2}}{V_{1}}$
Temperature: $\Delta S = nC\ln \frac{T_{2}}{T_{1}}$

Tony Ong 3K
Posts: 63
Joined: Fri Sep 28, 2018 12:23 am

### Residual Entropy

Why does NO have greater residual entropy than BF3 at 0K???

Fanny Lee 2K
Posts: 73
Joined: Fri Sep 28, 2018 12:29 am

### Re: Residual Entropy

NO can pack as NO or ON which are clearly identifiable whereas the three F positions in BF3 cannot be distinguished.

KimGiang2F
Posts: 31
Joined: Fri Sep 28, 2018 12:19 am

### Re: Residual Entropy

At 0 K, NO has a greater residual entropy than BF3 because NO can be oriented as both NO and ON; BF3, no matter how you rotate the molecule, will look the same, because the F's are symmetric around the B. Therefore, NO has higher residual entropy, because it takes upon more orientations.