@mike_malaska@deepspace.social
2026-03-11 01:22 UTC
A key is understanding how things dissolve.
For boring solids, like salt or sugar dissolving in water, the more you heat the water, the more stuff (most salts {with NaCl being exception}, sugar) can go into solution. Cool it, and you can crystallize it out.
Fun edible demo? make your own rock candy by crystallizing out sugar
Instructions here: https://wearenotmartha.com/make-your-own-rock-candy/
But...calcium carbonate (and other carbonates) are weird.
Replies (1)
-
@mike_malaska@deepspace.social 2026-03-11 01:26
Calcium carbonate has a complex equilibrium that depends on CO2 dissolving in water to make carbonate anion. Bottom line: the MORE CO2 dissolved, the MORE Calcium carbonate will dissolve in water. Those fun cave formations? Saturated CaCO3 waters full of CO2 drip into a cave. The CO2 escapes the water, lowers CaCO3 solubiility, now super-saturated CaCO3 (limestone) precipitates out. Cave formations!!! Straws, stalactites, stalagmites (bounce), helictites, rimstones, etc.