## Crystal Problem on Quiz 1

Boltzmann Equation for Entropy: $S = k_{B} \ln W$

Jaime_Chamberlain_3G
Posts: 23
Joined: Sat Jul 09, 2016 3:00 am

### Crystal Problem on Quiz 1

Can someone please explain the Crystal problem from quiz 1? How are both the crystals not perfect? Thank you.

Jamie_Lin_3I
Posts: 25
Joined: Sat Jul 09, 2016 3:00 am
Been upvoted: 2 times

### Re: Crystal Problem on Quiz 1

Hello!
I'm not sure if we had the same question or what you meant by perfect.
But if you're referring to the question about which molecule, H2O or HOCl, has larger molar entropy at T=0 K, then HOCl would have a larger molar entropy. This is because the two atoms attached to O in H2O is the same, which allows no disorder at T=0K. However, HOCl has two different atoms that can have different microstates at the molecular level with the same energy. Thus, even at T=0 K, HOCl still has residual disorder due to the different atoms attached to O.