The Debunker: Does Hot Water Freeze Faster Than Cold Water?
T. S. Eliot wrote that “April is the cruelest month,” but January brings the Northern Hemisphere its cruelest temperatures of the year. We’ve asked ex-Jeopardy! champ Ken Jennings to come in from the cold and put a chill on some of the most persistent cold-weather myths he could think of. You shall know the truth and the truth shall set you freeze (yes, we stole that from Arnold Schwarzenegger’s dialogue in Batman and Robin.)
Icy Myth #4: Hot Water Freezes Faster Than Cold Water.
It’s a common bit of scientific trivia that, for some mysterious reason, hot water freezes faster than cold water. In general, that’s not true—and would violate the laws of thermodynamics if it were. Think about it this way: for a container of hot water to freeze before a cold one does, it would have to be losing its heat at a faster rate. Why would it do so? And even if it did lose enough heat to “catch up” to the cold sample, the two containers would then be identical, right? Why would the initially-hotter water “remember” its past and continue to cool off faster?
