Before reading this articles a lot of people will find the question a little bit stunning, which is the main reason why I develop a lot of interest by explaining unveiling the misery as much as possible. If you are one of those that still find this to be stunning, you are not the first person to feel this way, a lot of researchers have also been to this state before. The question you might want to ask is how does this work, well don't be in a hurry, stay comfortable as you read and assimilate.
Erasto Batholomea Mpemba was one of the earliest researcher that published an article about how hot water tend to freeze faster than a cold water. Mpemba observation that lead to this whole scenario is as a result of his experience he had in form 3 at magamba secondary school, Tanganyika. Where he got to discover that his own hot ice mix cream placed in the the freezer along side his colleagues own which where cold before got freeze faster than his colleagues mix ice cream which were allowed to get cold before it was placed in the freezer. After this repeated action by his physics teacher Osborne at his placed of work then they both made a publication which was later named after his name as mpemba effect which is what is still known uptil today.
Before explaining further it should be noted that there are some extreme cases where by a cold water will get freeze much faster than a hot water, that is in case like when the temperature of the hot water is as high as 100 degree Celsius and the cold water is at 0.9 degree Celsius this kind of cases is a complete different cases.
Based on the research carried out by Vynnycky and Mitchell the result of the research also indicated that at 80 degree Celsius of water will freeze exactly the same time with a water at 10 degree Celsius if the cooling temperature for both is at -10 degree Celsius.
In other not to get carried away on temperature of the water alone, there are more than one factor that make a water cool much more faster which are as follows;
Evaporation: it should be noted that evaporation is one of the determining factor which help in explaining the reasons why a hot water get freeze much more faster than a cold water. This simply means that hot water tend to have high water vapor than warm water, this water vapor pressure help to boost the rate at which the water actually get frozen. According to other researcher made this does not explain fully the reason why hot water tend to get frozen faster.
Dissolved gas: it is said that water tend to hold much more dissolved water which makes it easy to develop convection current thus water get cooled easily.
Convection: accelerating heat transfer,reductionof water density below 4 degree Celsius(39 degree Farenheit) tends to surpress the conviction current that cool the lower part of the liquid mass;the lower density of hot water reduced the effect perhaps sustaining the more rapid initial cooling.
Surrounding: The initially hot water may change the environment around it in some way that makes it cool faster later on. One experiment reported significant changes in the data simply upon changing the size of the freezer that the container sat in . So conceivably it is important not just to know about the water and the container, but about the environment around it.
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Finally here is what a physics team from nanyang technological university in Singapore led by xi zhang say about this situation. According to this team they said water is made up of one oxygen atom bonded covalently to two hydrogen molecules. When the water is very hot the bond between this chemical molecules tend to stretch of which make it much more easier and faster to shrink there leading to a freeze. These was one of the research that tend to explain mpemba effects of how hot water tend to get freeze faster than cold water.
If there is any part you still find difficult to understand feel free to ask via the comment section, if you don't ask then i assume you understand every part of the article. Have a wonderful time on steemit and remain blessed.
Materials Used For Carrying Out Research
[1]Can hot water freeze faster than cold water?
[2] Mpemba effect
[3]Why Hot Water Freezes Faster Than Cold—Physicists Solve the Mpemba Effect
[4]Does Hot Water Really Freeze Faster Than Cold Water?
[5]Hot water freezes faster than cold - and now we know why.
[6]Evaporative cooling and the Mpemba effect
[7]Questioning the Mpemba effect: hot water does not cool more quickly than cold
[8]Does Water Expand or Contract When Heated?
