Supercooling and Superheating

We all know that freezing point of water is 32℉(0℃), which means that the liquid freezes, but sometimes science goes crazy. Supercooling, also know as undercooling, is this concept and means that if you go to a certain low temperature, a liquid will not turn into a solid. Pure water normally freezes at 32 F, but the temperature of supercooling pure water is -55℉(-48.3℃). Droplets of supercooled water often appear in cumulus clouds and stratiform.
A liquid below its freezing point will crystallize in the presence of a seed crystal or nucleus around which a crystal structure can form. However, lacking any such nucleus, the liquid phase can be maintained all the way down to the temperature at which crystal homogeneous nucleation occurs. The homogeneous nucleation can occur above the glass transition where the system is an amorphous—that is, non-crystalline—solid.
 If cooled at a rate on the order of 10⁶ K/s, the crystal nucleation can be avoided and water becomes a glass.


If you totally did not understand was was states above, here is the vocabulary section.
Vocabulary 
Stratiform - Stratus Cloud
Crystallize - to form in crystals
Seed - nucleus
Nucleation - to form (something) in the nucleus
Amorphous - no particular shape


They form into ice when they are struck by the wings of passing airplanes and abruptly crystallize. Freezing Rain is also caused by supercooled droplets. Some plants are able to supercool the fluid in their cells cytosol and vacuole and thereby survive temperatures down to −40 °C.
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The other concept we will be talking about is pretty much the opposite of supercooling, it is superheating. You might of guessed what it is. We know when you have a pan, add water to it, and heat it up to 212℉, you have boiling point, but it is just like supercooling. Superheating is when you heat it enough to not boil but at a high temperature. In other words, superheating is when you heat something in a chamber, setting the temperature above 212℉, and it will boil, but no water vapor is emitted. If something is say 500 degrees superheat, that means that no water vapor can be present at this pressure by 100 degrees. But some pressure is applied or needed.Superheating is achieved by heating a humongous substance in a clean container, free of nucleation sites, while taking care not to disturb the liquid.A liquid is sometimes observed not to boil even though its vapor pressure does exceed the ambient pressure. The cause is an additional force, the surface tension, which suppresses the growth of bubbles.


Now you can introduce to your friends what superheating and supercooling is, hope you have fun!