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Water loses heat at a constant rate when cooled, so hotter water will normally take longer to freeze, having more energy to be removed.
The Mpemba Effect is a special phenomenon where hot water freezes faster than cold water. The discovery of this effect was made by a high school student named Mpemba in Tanzania, Africa in 1963. He noticed this phenomenon while making ice cream and was curious enough to make note of it. His teachers did not believe it was possible, and it took several years until university professors finally accepted his discovery.
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Is it true that hot water freezes faster than cold water?
Hot water does not freeze faster than cold water. Nor does cold water boil faster than hot water. For water to freeze, you must remove enough heat to bring its temperature down to 0 C. The colder the water is, the less heat you have to remove before it freezes. I have no idea why this rumor is cirulating the net and the world. It is just totaly insane to even think that that could be true. If you have just heated the water to 100 degrese, then it has that much more to cool down to 0. If the waterisat 30 then it is obvious that the 30 degree would cool faster. Really now. It's not exactly a rumor, it's true...at least sometimes. In scientific communities it's called "The Mpemba Effect" and was named after a Tanzanian student named Erasto Mpemba who first raised the question in the late 60s. When a container of water is placed in a freezer, there are many factors which can affect the length of time it will take to freeze, and under the proper combination of circumstances, a given volume of hot water in a container may freeze faster than the same volume of cold water. So, the best answer is, "Sometimes."
For water in glass plastic or styrofoam cups - which will freeze fastest?
Assuming they are the same or similar shape and volume, water in glass would freeze first, then plastic then foam. Foam allows transfer of heat out of water more slowly than plastic and the glass probably has the highest rate of heat radiation of the three.
Why cant liquid water at 273.3 k will not freeze in terms of gibbs energy?
Water cannot freeze at 273.3 k in terms of gibbs energy because when absolute zero (Which is 273.3 k or 0 celcius) is achieved than the water will be at equilibrium, which means that the water melts at the exact same rate the water freezes. Absolute zero has not been achieved, so there is no example of this.
Why does boiled water freeze faster?
A perverse observation is given the name of Mpemba Effect, in which a warm liquid freezes more quickly than a cool one. An on-line encyclopedia should list thehistory and the explanations. The effect is real and repeatable. [The associated story I most like was of the professor's lab assistant being asked for the results of his investigations so far. His response was "So far, sir, the warm liquid has always frozen faster than the cool one, but I will repeat the experiment until I get the right answer.']
What is meant by BOD loading rate?
BOD loading rate is the amount of organic matter added in water or waste water for example sewage water
Do hot water pipes freeze faster than cold water pipes?
Why is the second paragraph a contradiction of the first? If hot water pipes 'Absolutely' do not freeze faster than cold water pipes then why the comment about the cold water pipes having a larger diameter which causes them to freeze at a slower rate than the smaller hot water pipes? Also, the word then in the last line should be thanand there should be an a between usually and larger. And, piping should be changed to pipe.
Does soda juice or water freeze at the same rate?
Yes all liquids freeze at the same temprature, although the boiling rate is affected by impurities.
Which water freezes the fastest colored water on plain water and why?
they both freeze the same rate
Does soda juice or water freeze at the same rate for variables?
Water takes longer
What has a higher rate of evaporation hot water or cold water?
A higher rate of evaporation has hot water.
How come liquids don't freeze at the same rate?
OK well, liquids expand at cold temperature while other matter contracts at cold temp. so the liquids expand and turn into ice. I need more info, How come liquids don't freeze at the same rate as what
Does salt water freeze at the same temperature as normal water?
no, because if you put saltwater and freshwater in the freezer saltwater will not freeze completely ,because it has salt in it and it will not freeze at the same rate as freshwater that is my answer to this question.
Effect of facial immersion in cold water on heart rate and blood pressure?
the heart rate decreases, to a low rate oof 20 to 30 beats per minute. especially in cold water.
How does cold water affect how salt dissolves?
Cold water simply slows down the rate at which salt dissolves.
Which will freeze the faster between salt water sugar water and tap water?
Tap Water because adding substances to the water (salt or sugar) reduce the rate at which water will form ice crystals, making it freeze at a lower temperature.
What is a dependent variable for breathing rate of goldfish in cold water?
its the respiration rate of the goldfish.
Why does cold water freeze fastest then room temperature water and lastly warm water?
Because given that colder air is removing heat from the water, there is more energy to remove from the warmer water. The RATE of cooling is constant regardless of the initial temperatures of either the water or the air. Except for the following : The freezing of water requires two different reductions in heat. You first lower the temperature to 32°F (0° C). At that point the water will not spontaneously freeze, because molecular motion has to stop for ice crystals to form their orderly lattice. This is easily observed when cooling water in a very cold environment : the temperature will drop steadily and at the same rate until it reaches 32°F, at which point the decline will halt temporarily until ice crystals are formed. Once the water is entirely ice, the ice's temperature will resume its former rate of cooling. The heat required to melt ice or freeze water at its freezing point is called the "heat of fusion", and a similar but varying heat is required for all other substances that experience a change in state from liquid to solid.
