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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Generally, heating raises the energy of a substance by lengthening and softening all bonds involved. 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!

Efecto Mpemba by Mir Lr on Prezi

Sign in to get notified via email when new comments are made. The warm water cools faster than the cool water at first. Can you explain that water at the bottom of a lake in winter is almost efecfo at 4 degrees C? Stop pushing pseudoscience on a science site. That’s because water is at its maximum density at that temperature.

There’s a number of possible explanations out there. Consistency between predictions and measurements revealed that mpemva tau drops exponentially effecto with the initial temperature of the water being cooled. How am I an idiot? Thus formerly warm water has some stronger convection going on compared to cold water even when the formerly warm water is at or below the same temperature as the cold. Back to square one, wealthychef. H nonbond in water efevto actively the general rule of thermal expansion and drives the H-O covalent bond to relax oppositely in length and energy because of the inter-electron-electron pair coupling [J Phys Chem Lett 4, ; ibid 4, ].


You mpembs to talk about that crap, go to a homeopathy website. Researchers from the University of Amsterdam have discovered that machines just one molecule in size move far quicker if you add a ‘lubricant’ to their surroundings. Pine needles from old Christmas trees could be turned into paint and food sweeteners in the future December 27, Abandoned Christmas trees could be saved from landfill and turned into paint and food sweeteners according to new research by the University of Sheffield.

For example, it could be used to make electronic devices which we want to cool faster.

Mpemba effect

It takes more time to release more energy. The Mpemba effect is a process in which hot water can freeze faster than cold water. From experimental data Kell determined that this effect was beyond the scope of Newtonian cooling and attributed the higher rate of temperature loss for water at sufficiently high temperatures as being the result of evaporation.

The researchers, who have recently published the findings in Physical Review Letters, have confirmed how this phenomenon occurs in granular fluids, that is, those composed of particles that are very small and interact among those that lose part of their kinetic energy.

Mpemba Effect in Granular Fluids. How is it possible, the homeopathy works even under the dilutions, which would allow no molecule of the active chemical in the solution?

Learning to emulate and use this effect might have applications in our daily life, according to scientists. Physical Chemistry Chemical Physics. Now, the team in Singapore appears to have solved the riddle—it’s due, they claim, to the small amount of energy stored in stretched hydrogen bonds.


I suppose they need to define the temperature of warm and if the water was once boiled or not. Sorry, I didn’t realise who “zephir” was.

Inthe Royal Society of Chemistry held a competition calling for papers offering explanations to the Mpemba effect. The convection increases the rate of heat loss for the formerly warm water compared to the cold, and hence the formerly warm water cools and freezes faster than the cold water. This provides a momentum for the more mpekba crystallization of the warmer water into ice, versus that of the cooler water.

Hot water does not cool more quickly than cold”. They published the results mpwmba inwhile Mpemba was studying at the College of African Wildlife Management. By the time the “warm” water has cooled to the temperature of the “cool” water, I would think the convection in the previously warm water will be the same as in the cool water.

That is really a nonsensical statement. But there is a difference. In fact, this group of researchers is planning to carry out mepmba experiment that verifies the theory. Does warm water freeze at a higher temperature than cold water IE it has to give up less energy?

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