CHEMISTRY COMMUNITY

What causes a substance to superheat or supercool? Is this common?

When a gas or vapor is above its boiling point, it is said to be superheated. Supercooling is the melting of a solid above its freezing point which is very difficult because most times, the solid will almost always melt at the same temperature for a given pressure.

Superheating, or boiling delay occurs when a liquid is heated past its boiling point without actually boiling. This normally only occurs in homogeneous substances.

I don't think superheating or supercooling is very common, but there are multiple different variables that can cause them to happen. One example of superheating is how when you microwave water in a glass bowl, the temperature must be greater than 100 degrees C in order for the water to boil. This is because containers with a smooth surface and the relatively static heating environment inside a microwave oven prevent steam bubbles from forming.

Hi Abby! What I learn is that superheating describes the phenomenon when a liquid is heated to a temperature above its boiling point,without boiling and vaporizing. When the temperature of a liquid is below the freezing point but the liquid doesn't become solid, this phenomenon is called supercooling. Both situations are very rare.

Nice question. Superheating is when something goes over its boiling point without actually boiling!

Are there any other examples of superheating besides the microwave one?