How to Boil Water Until it Freezes
No, this isn't a joke. You can actually boil water until it freezes solid, given the right conditions. Cody of Cody's Lab walks us through the whole process.
So what's the science behind it? First, you'll need a pressure chamber to remove the air. Cody placed a beaker with 60 ml of room temperature tap water into the chamber. He then adds a magnesium sulphate salt and a calcium-sulphate coated bottle into the back of the chamber. These substances only absorb the water vapor as to not damage the pressure chamber. Solid calcite is added to the water as boiling chips.
A liquid's boiling point depends on both pressure and temperature. The warmer the liquid, the higher the vapor pressure. Cody started removing the air from the chamber and lowering the pressure, thus lowering the boiling temperature. Eventually, the boiling temperature gets lower than the water temperature.
Via Cody's Lab