Question

Why does water disappear from an open container?

Answer 1

Magic....?

Explanation:

You have examined the physical process of evaporation.....i.e.

`H_2O(l) rightleftharpoonsH_2O(g)`

Now you had an open system, and the water vapour (or ethanol vapur, or whatever the solvent was) could expand to fill the room, and over 24-48 hours it entirely evaporated. Now you started with a solution, in which there was some involatile solute (what does `"involatile"` mean?).

The solute came out of solution as the water (?) slowly evaporated, to give a solid residue.....

I bet the stuff was copper sulfate, which forms lovely blue crystals of `CuSO_4*5H_2O` on crystallization.....