Erasto MpembaIn thermodynamics, Erasto Mpemba (1950-) is a Tanzanian, African amateur scientist noted for his circa 1962 observation that “warm-freezes-faster” in respect to ice cream making, about which he began to query people for an answer, eventually finding physics professor Denis Osborne, who published an article in 1969 with him on this phenomenon.

See main: Mpemba effect
In 1961 (age 7) (Ѻ) or 1963 (age 9) (Ѻ), Mpemba, while making ice cream, noted the phenomenon — also commented on by Aristotle, Roger Bacon, Francis Bacon, and Rene Descartes — that “warm-freezes-faster”, meaning that if he heated his water (or cream) before freezing, he could make ice cream faster. Mpemba told his teachers about this, who at the time, supposedly, laughed at him.

In 1966, Mpemba entered into Magamba Secondary (High) School, where he had a chance meeting with noted physics professor Denis Osborne from the University College in Dar Es Salaam. After an Osborne lecture, Mpemba boldly asked the physicist:

“If you take two similar containers with equal volumes of water, one at 95°F and the other at 212°F and put them into a freezer, the one that started at 212°F freezes first. Why?”

In 1969, Osborn co-authored with Mpemba this experimental phenomena, which thereafter became dubbed the Mpemba effect, i.e. the hot-begets-cold-quicker phenomenon, that lays question to Newton's law of cooling, one of the supposed big seven paradoxes of thermodynamics. [1]

Erasto Mpemba and Denis Osborne (London, 2013)
Erasto Mpemba (left) and Denis Osborne (right) in London (2013). [4]
By 1972, Mpemba was considered a noted expert, so to speak, on rate of cooling theories. [2]

In 1979, Mpemba was associated with the College of African Wildlife management, Moshi, Tanzania. [3]

See also
Social Mpemba effect

1. (a) Cucic, Dragoljub. (2009). “Paradoxes of Thermodynamics and Statistical Physics” (abs),, Dec 09.
(b) Mpemba, Erasto B.; Osborne, Denis G. (1969). "Cool?". Physics Education (Institute of Physics) 4: 172–175.
2. Mpemba, Erasto B. (1972). “Rate of Cooling”; in: Teaching School Physics (pgs. 71-) by John Lewis, Penguin.
3. Mpemba, E. B.; Osborne, D. G. (1979). “The Mpemba effect.” Physics Education (Institute of Physics) 14: 410–412.
4. Whipple, Tom. (2013). “22,000 scientists still can’t explain the boy who kept his cool” (Ѻ), The Times, Jan 11.

● Anon. (2013). “The Mpemba effect: Erasto Mpemba and Denis Osborne” (Ѻ), Royal Society of Chemistry, Jan 10.

External links
● Erasto Mpemba (SpanishEnglish) – Wikipedia.
Erasto Mpemba –
Who was Erasto B. Mpemba? (chemistry) –

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