Why boiling water cools faster than a non boiling water in a fridge?

Answer 1

To understand what is going on here you need to be explained some basic principles of heat transfer.

1.The rate of heat transfer increases as the difference in temperature between the two mediums increases.

2. The heat is being transfered out of the water and into the enviroment of the refrigerator.

3. The heat is then being transfered into the cooling coils (freon in coils) and being exhausted out the back of the refrigerator.

The reality is this. If you were to put boiling water and water at 50 F into the same enviroment say at 34 degrees the water at 50 would reach equilibrium with it enviroment first. That is one of the basic principles of thermodynamics....So what is happening in your refrigerator to make boiling water cool faster? The answer is simple. By putting water into your fridge at such a drastically high temperature you are forcing your refrigerator to work much harder (i.e. the compressor in the back of the fridge) to cool the boiling water. So although it seems as though boiling water cools down faster in a normal enviroment than room temperature water it really does not. The refrigerator is just working much harder to get it to that temperature.

If you don't believe this try an experiment boil water and then take it off the heat and let it sit outside in the cold weather. Take water from the tap and let it sit outside in a seperate container. The water from the tap will reach equilibrium with the outside temperature before the boiling water does.

I hope i've helped you some

Answer 2

I agree. Also, when the water is boiling, it begins to evaporate, causing the molecules to move farther away from each other. So, it cools faster because the molecules have a lot of space. In the liquid phase, the molecules are closer together, so it takes a while to cool.

Answer 3

It evaporates quickly reducing both the temperature and the volume. As the volume decreases below the level of the other water, the temperature will drop faster.

Answer 4

As the hot water cools, it loses mass to evaporation which forms water vapor. With less mass, the liquid has to lose heat to cool, and so it cools faster.