## Entropy

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

Bola_G_3H
Posts: 12
Joined: Wed Sep 21, 2016 2:56 pm

### Entropy

What effect does the being reversible vs irreversible have on entropy? How would you calculate both?

Kathy Vu 3L
Posts: 24
Joined: Fri Jul 15, 2016 3:00 am

### Re: Entropy

Irreversible processes cause a change in entropy, whereas reversible processes have an entropy change of 0.

stephanieyang_3F
Posts: 62
Joined: Wed Sep 21, 2016 2:55 pm

### Re: Entropy

Kathy can you explain what you mean by that? What kind of example should we refer to understand that concept?

Posts: 23
Joined: Wed Sep 21, 2016 2:59 pm

### Re: Entropy

If entropy is always increasing, then in a non-spontaneous reaction what part of the reaction relates to the increase in entropy if we are using work to create order?

Emma Cole 3F
Posts: 13
Joined: Wed Sep 21, 2016 2:59 pm

### Re: Entropy

I understand that with a more massive substance, the higher the entropy. But, how can you distinguish in the level of entropy between a solid, a liquid, and a gas of the same substance?

stephanieyang_3F
Posts: 62
Joined: Wed Sep 21, 2016 2:55 pm

### Re: Entropy

Usually entropy increases from solid -> liquid -> gas because there's more disorder associated with a gas (molecules are free to move around and are not bounded) compared to that of a solid (molecules are in rigid structures).

shreya_mantri_3I
Posts: 17
Joined: Fri Jun 17, 2016 11:28 am

### Re: Entropy

Does anyone know what effect does pressure have on entropy?

stephanieyang_3F
Posts: 62
Joined: Wed Sep 21, 2016 2:55 pm

### Re: Entropy

A higher pressure would mean that a substance is more constricted to move around. The entropy would therefore be less when the pressure increases.