Question

Would you expect a dynamic equilibrium in a liquid in an open container?

Answer 1

Probably not....

Explanation:

We consider the equilibrium phase change, say...

`"Liquid "rightleftharpoons" Vapour"`

And this is generally a function of temperature....water for instance at a given temperature exerts a equilibrium vapour pressure, at `298*K` the so-called `P_"saturated vapour pressure"=23.8*mm*Hg`. In higher level calculations, where a gas is collected over water, we subtract `P_"SVP"` from the measured pressure.

Now in an open container, the liquid water (or other liquid) will slowly evaporate, and the container will empty eventually. In a closed container, there is dynamic equilibrium between the vapour phase, and the liquid phase, and the rate of evaporation is equal to the rate of condensation.

Of course for water, `P_"SVP"=1*atm` AT `100` `""^@C`. Why should this be so?