## Entropy between molecules

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

Chloe Alviz 1E
Posts: 102
Joined: Sat Aug 17, 2019 12:17 am

### Entropy between molecules

Given two different molecular formulas, how would we determine which one has a higher residual entropy?

Brian Tangsombatvisit 1C
Posts: 119
Joined: Sat Aug 17, 2019 12:15 am

### Re: Entropy between molecules

More complex and larger molecules have higher residual entropies, since they have more vibrational/rotational modes and possible states of arrangements. Also, all molecules in the gas phase have more residual entropy than all molecules in the liquid phase, which all have more entropy than molecules in the solid phase.

Skyllar Kuppinger 1F
Posts: 52
Joined: Thu Jul 25, 2019 12:16 am

### Re: Entropy between molecules

it is based on the size and how complicated the structure is. If there are two molecules of equally complex structure then the larger one has higher residual entropy bc more atoms=more electrons and electrons are always moving around so they have many different possible states. if its 2 diatomic molecules then the one with the bigger atom/element has higher entropy. As for the structure, a molecule like methane (all the atoms surrounding the central carbon are hydrogen) would have lower residual entropy than a molecule where there is more than one type of element/atom surrounding the central atom.

Mai V 4L
Posts: 111
Joined: Fri Sep 28, 2018 12:23 am

### Re: Entropy between molecules

Skyllar Kuppinger 1F wrote:it is based on the size and how complicated the structure is. If there are two molecules of equally complex structure then the larger one has higher residual entropy bc more atoms=more electrons and electrons are always moving around so they have many different possible states. if its 2 diatomic molecules then the one with the bigger atom/element has higher entropy. As for the structure, a molecule like methane (all the atoms surrounding the central carbon are hydrogen) would have lower residual entropy than a molecule where there is more than one type of element/atom surrounding the central atom.

How can you tell if they are equally complex or not?

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