Is it true that when making ice cubes, hot water freezes quicker than cold?

Kainantu

It is called the Mpemba effect. The why is not yet known. Hot water can in fact freeze faster than cold water for a wide range of experimental conditions. It has been known for centuries, and was described by Aristotle, Bacon, and Descartes. The phenomenon that hot water may freeze faster than cold is often called the Mpemba effect. The main problem is that the time it takes water to freeze is highly sensitive to a number of details in the experimental set- up, such as the shape and size of the container, the shape and size of the refrigeration unit, the gas and impurity content of the water, how the time of freezing is defined, and so on. Because of this sensitivity, while experiments have generally agreed that the Mpemba effect occurs, they disagree over the conditions under which it occurs, and thus about why it occurs. Very good explanation at this site: http://math.ucr.edu/home/baez/physics/General/hot_water.html May 12 03, 12:51 AM