Hot Water Can Freeze Faster Than Cold Water
Under certain conditions, hot water can freeze faster than cold water, a phenomenon known as the Mpemba effect.
About this fact
The Mpemba effect is a counterintuitive phenomenon where hot water freezes faster than cold water under certain conditions. Named after Erasto Mpemba, a Tanzanian student who observed this in 1963, the effect has been documented but not fully explained. Several theories attempt to explain it: hot water evaporates faster, reducing the volume to be frozen; dissolved gases escape from hot water, changing its properties; convection currents in hot water may aid heat transfer; and hot water may form different crystal structures. The effect doesn't always occur and depends on specific conditions like container shape, volume, and environmental factors.