Keith_W
Major Contributor
Re: pop rocks. This is not humour, but it is interesting:
TLDR: pop rocks are made by forcing carbon dioxide to dissolve into molten sugar. You need a complicated contraption that can supply enough heat to keep sugar molten, keep it under pressure, and a vacuum pump to remove the air and flood the chamber with CO2. When the sugar solidifies, the CO2 has no way to escape unless it is dissolved in water.