Whenever I leave sugar in hot water, it always form a distinct transparent layer from the water above. After I stir it, the remaining sugar will form a less distinct layer. Why don’t the layers diffuse onto eachother? Can anyone explain this?
Whenever I leave sugar in hot water, it always form a distinct transparent layer from the water above. After I stir it, the remaining sugar will form a less distinct layer. Why don’t the layers diffuse onto eachother? Can anyone explain this?
How can they stay separated for so long?
For the same reason that saltwater can remain separate from fresh water, or even hot water and cold water - diffusion is typically a slow process, particularly if you do not stir, or otherwise mix the substances.
Consider this: drop a single drop of food dye into a glass of water. There’s no way the entire glass immediately turns into the relevant colour, it takes time for the molecules to move about.