## pure substance

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Nan_Guan_1L
Posts: 92
Joined: Wed Sep 30, 2020 9:59 pm

### pure substance

can anyone recall why isn't gas considered a pure substance but solid and liquid are? I think Dr. lavelle mentioned in lecture but I can't quite recall. Thank you!

Karl Yost 1L
Posts: 171
Joined: Thu Dec 17, 2020 12:19 am

### Re: pure substance

I believe that the purity of a substance isn't affected by the state of matter. This link should help clear up some confusion:

https://chem.libretexts.org/Courses/Los ... d_Mixtures

LReedy_3C
Posts: 92
Joined: Fri Aug 30, 2019 12:17 am

### Re: pure substance

I think we were just told to assume that a liquid is a pure substance while we can't make that assumption about a gas, and that's why aqueous solutions are considered but the liquid they are assumed to be in isn't

Brennan McGurrr 3C
Posts: 90
Joined: Wed Sep 30, 2020 9:47 pm

### Re: pure substance

Gases are always part of the equilibrium expression because if it is not a pure gas, it is a mixture of gases with measurable concentrations. If it is a pure gas, the pressure can still be measured.

605291562
Posts: 91
Joined: Wed Sep 30, 2020 10:07 pm

### Re: pure substance

I don't think gasses cannot be pure, I think we just cannot assume that they are where as he told us that we could assume liquids are pure.