Pure Substances

[305174946]

In lecture we discussed how liquids and solids were not included in the chemical equilibrium equation because they were pure substances. Can someone please explain why gases are not pure substances.

[505095972]

I think it is more significant that gases effect activity (which is a concept that is a little more complicated so Dr. Lavelle said we don’t need to really focus on it) and activity is how equilibrium constants are found so therefore gases explain equilibrium constants.

[Michael Novelo 4G]

Pure substances can't be separated into other substances. Air for example is a mixture of different gases so it is not 'pure'. Pure substances are also made of the same material throughout so a solid and liquid are physically the same throughout I believe.