What's Up With That: The Mysterious Effect That Makes Hot Water Freeze Faster Than Cold

This winter was really, really cold. Beer in a Hot Pan Slides Around Like an Air Hockey PuckPart of the fascination with this experiment is that the air is so cold that even extremely hot water immediately turns to snow. But there’s another extremely bizarre effect going on that deserves a closer look: Something about hot water makes it freeze faster than cold water. When a professor of physics later came to visit the class, Mpemba asked him if it was possible for hot things to freeze faster than cold ones. They put two glasses of water, one at 95 degrees Fahrenheit and the other at boiling, in a freezer and noted that the hotter one turned faster to ice.