## Residual Entropy

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

305174946
Posts: 61
Joined: Fri Sep 28, 2018 12:17 am

### Residual Entropy

In lecture Lavelle did an example using four carbon monoxide molecules and mentioned that there is no translational/rotational movement and I was wondering what else must be stagnant for this system to have residual entropy?

Maria Solis Disc 1G
Posts: 63
Joined: Fri Sep 28, 2018 12:27 am
Been upvoted: 2 times

### Re: Residual Entropy

I honestly do not know what residual entropy is, but Dr. Lavelle mentioned rotational state, translational state, vibrational state, and an electron's state in the actual atom.

Alexa_Henrie_1I
Posts: 61
Joined: Fri Sep 29, 2017 7:03 am

### Re: Residual Entropy

Residual entropy is positional entropy. We can find it using SkblnW (this ignores thermal energy).

Rami_Z_AbuQubo_2K
Posts: 89
Joined: Thu Jun 07, 2018 3:00 am

### Re: Residual Entropy

Do more orientations mean a greater residual entropy?

Posts: 37
Joined: Fri Sep 28, 2018 12:22 am
Been upvoted: 1 time

### Re: Residual Entropy

Yes, more possible positions leads to greater residual entropy. Since the equation is delta S= Kb ln W and W is the number of states raised to the number of molecules in the system, the increase in the number of states increases W and therefore increases entropy.

Posts: 37
Joined: Fri Sep 28, 2018 12:22 am
Been upvoted: 1 time

### Re: Residual Entropy

I was wondering if the only time you use the equation delta S=Kb ln W is if you are calculating positional entropy?

Return to “Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy”

### Who is online

Users browsing this forum: No registered users and 1 guest