dewiki Mpemba-Effekt; elwiki Φαινόμενο Mpemba; enwiki Mpemba effect; eowiki Mpemba-efiko; eswiki Efecto Mpemba; etwiki Mpemba efekt; fawiki اثر امپمبا. Erasto Mpemba, a los 13 descubrió el efecto como consecuencia de una tarea, en Iringa, Tanzania, más adelante comprobó su teoría en El efecto Mpemba segun Nikola Bregovic – Download as PDF File .pdf), Text File .txt) or read online.

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They ruled out loss of liquid volume by evaporation as a significant factor and the effect of dissolved air.

Physical paradoxes Thermodynamics Phase transitions Unsolved problems in physics Water physics Physical phenomena Hysteresis. Your explanation does not make sense at least to me. Ever try to grow crystals when you were a kid? That is why, the researchers say, it freezes faster than cool water.

H nonbond in water follows actively the general rule of thermal expansion and drives the Mpeba covalent bond to relax oppositely in length and energy because of the inter-electron-electron pair coupling [J Phys Chem Lett 4, ; ibid 4, ]. Retrieved from ” https: Physics Worldpp. The website of the University Carlos III of Madrid use its own cookies and third-party cookies to improve our services by analyzing their browsing habits.

The fact that preheated liquids freeze faster than those that are already cold was observed for the first time by Aristotle in the 4th century AD. Evaporation was controlled for. Spewing a bunch of words does not imply that you are right unless proven wrong. Philosophical Transactions of the Royal Society of London.

Abstract We demonstrate that the Mpemba paradox arises intrinsically from the release rate of energy initially stored in the covalent H-O part of the O: The required vast multidimensional array of experiments might explain why the effect is not yet understood.


Just that VendicarE’s claim can’t be mlemba out of hand. No, don’t think so.

Researchers claim to have discovered why warm water freezes faster than cooler water

A reviewer for Physics World writes, “Even if the Mpemba effect is real — if hot water can sometimes freeze more quickly than cold — it is not clear whether the explanation would be trivial or illuminating. I would imagine true experts in the field pertaining to each article would most likely have read about it already in the source journal, as part of their profession.

We only “know” it because people keep insisting it does. Enthalpy of fusion Enthalpy of sublimation Enthalpy of vaporization Latent heat Latent internal energy Trouton’s ratio Volatility.

Perhaps scientists working in very specific fields enjoy reading about advances in other fields they wouldn’t normally have the time to read. This effect is formulated in terms of the relaxation time tau to represent all possible processes of energy loss.

Why can hot water freeze faster than cold water? | UC3M

And Efetco, Teech’s mumbo-jumbo explanation does not explain this, or make any sense mpembw all for that matter. Can you explain that water at the bottom of a lake in winter is almost always at 4 degrees C? American Journal of Physics. The phenomenon, when taken to mean “hot water freezes faster than cold”, is difficult to reproduce or effecto because this statement is ill-defined.

That energy, the researchers suggest, is released as the water is cooled allowing the molecules to become closer to one another, and as every chemistry student knows giving up energy means cooling. There’s no room for crackpots and trolls here. He described it in in Form 3 of Magamba Secondary School, Tanganyikawhen freezing ice cream mix that was hot in cookery classes and noticing that it froze before the cold mix.


Perhaps water that was once boiled has less dissolved oxygen and gasses in it and freezes at a different rate. The warm water cools faster than the cool water at first.

The rate of cooling slows down so that one glass of water starting at C can never reach zero faster than one starting at 20 C because it has to get rid of more energy just to get to 20 C and at that point it will be cooling down no faster than the glass that started there!

This explanation makes sense. However, intwo research groups independently and simultaneously found theoretical evidence of the Mpemba effect and also predicted a new “inverse” Mpemba effect in which heating a cooled, far-from-equilibrium system takes less time than another system that is initially closer to equilibrium. H-O bond in water ice. Sorry, I didn’t realise who “zephir” was. The plain saying, that something doesn’t provide an explanation mpekba not enough.

They published the results together in efevto, while Mpemba was studying at the College of African Wildlife Management. The water can become super cooled below 0c edecto still be a liquid. If evecto heat or cool that water, it will expand! In layman terms, it seems what they’re saying can be likened to a rubber band: This has enabled them to understand what scenarios it is easier to efeco in, which is one of the main contributions of this scientific study.