Why when you evaporate coffee and store the steam until it becomes liquid again, the liquid no longer has the color of coffee?

Question

I did this experiment one day because I was curious, sorry if it’s a stupid question

In: Chemistry

Answer 1

Your experiment just accidentally invented distillation.

If you have water with stuff in it, when you heat it up, the steam is just pure water. The stuff is left behind when the water evaporates – so when it becomes liquid again, that liquid is just water. You could do this with coffee, tea, juice – or even milk, spaghetti sauce, jam, or yogurt. Anything with water in it. The steam coming off is pure water only.

This effect is why the ocean is so salty. Salt dissolves into rivers and lakes from the ground, and gets carried into the ocean. When the sun evaporates ocean water, the salt is left behind and just accumulates in the ocean.

This can be useful for making drinkable water out of sea water too, just boil or evaporate it and collect the condensation.

You use this effect when cooking every time you “boil down” a sauce or soup to make it thicker. That only happens because it’s not the whole sauce boiling away, it’s only the water *from* the sauce leaving, so the sauce left in the pan gets thicker and more flavourful as you remove water from it.