Hot water can freeze faster than cold water
Hot water can freeze faster than cold water.
Reviewed by the CurioVault curator · 8 October 2026 · Last updated 29 September 2026 · Editorial standards
Hot water can freeze faster than cold water. This is the Mpemba effect, named after Tanzanian student Erasto Mpemba who noticed hot ice-cream mix froze first in 1963. Aristotle noted it 2,300 years earlier. Scientists still debate why, with causes including faster evaporation, reduced dissolved gases, convection currents, and supercooling differences. In 2016, a Royal Society of Chemistry competition drew 22,000 entries trying to explain it. Under identical freezers, 35°C water has beaten 5°C water to ice in controlled tests. It defies intuition, and physics still has no single agreed explanation.
Sources & Further Reading
Connected Curiosities
Lightning is five times hotter than the surface of the sun
A bolt of lightning is five times hotter than the surface of the sun.
Water can boil and freeze at the same time
Water can boil and freeze at the exact same time.
Bananas are radioactive and you would need 10 million at once
Bananas are naturally radioactive.
This curio is written in original words for CurioVault. Facts themselves are not copyrightable, but our wording is. If you reuse, please credit CurioVault.co.