Have you ever wondered what is evaporation? Evaporation is simply a kind of vapourising process that happens as the water vaporizes into the gaseous phase. The surrounding air must not be too saturated with the sealing material. Therefore, when the molecules of the solvent mix with each other, they automatically transfer energy to each other depending upon how they interact with each other.
In case of solvents like water vapor and oil, the interaction is opposite to what is evaporation. So, in the case of water vapor, the molecules are bound together and hence, there is loss of kinetic energy or force. This is why a drop of oil droplets sink to the bottom. The solvent molecules on the other hand, are floating freely and have zero net charge. So, the more of these molecules are present, the less the kinetic energy or force is generated.
What is evaporation done by? Evaporative cooling is a process where the liquids pass through a porous membrane to produce vapour. The vapour traps the solvent molecules within it.
Now the process of evaporation actually reduces the total charge on the molecules. As the water molecules are trapped in the liquid vapour, they do not have their average size changed. So, the average size of the molecule remains unchanged as well. However, the rate of cooling is faster in case of solvent droplets than in case of water droplets.
Now let us see what happens when we mix water and alcohol. As the alcohol molecules attach to the water vapor, their average sizes too get changed. But then, their average kinetic energy also gets changed. Now if you mix the same amount of each substance, their average kinetic energy will be the same. So, the total amount of kinetic energy will remain the same.
The process of evaporation has a lot of benefits. For example, it helps in cleaning air ducts, industrial processes, and space heating systems etc. The process of evaporation reduces the amount of heat loss from the systems. The same thing happens in air cooling systems. The cooling liquid gets converted into a form of liquid gas which is again gradually cooled.
The process of evaporation reduces the amount of energy spent on keeping the fluid warm. In other words, the process of evaporation provides a way for keeping the fluid warm as well as removing heat from it. The amount of heat is removed from the water molecules due to the evaporation process. The evaporated water will end up as steam and it makes up about 70% of the heating power of an air cooler.
If you have a look at your refrigerator, you will notice that there are many times that the liquid water does not evaporate completely. This is because of the presence of small water vapour molecules. We can ignore them for a while and they do not cause any harm to us. But when these tiny molecules get combined with the large water molecules, evaporation takes place. The end result is that the larger molecules are left without any liquid and this leads to the development of mold and mildew on surfaces.
Evaporative cooling is also used in the manufacturing industry. In fact, most machines that generate electricity do so through the use of evaporation. This process is used especially to remove the moisture from lubricating oils. When the oil molecules are allowed to evaporate, the kinetic energy that was contained within the liquid oil is released.
Apart from this, the process of evaporation can be used to reduce the temperature of a liquid. This is especially useful when dealing with very cold liquids. For instance, if you are storing something in the fridge, it would be advisable to lower the temperature of this liquid to prevent it from getting warm. Similarly, the warm liquid should be allowed to escape from the metal containers using the evaporation process.
Evaporative cooling can also be used for the purification of water. In such a process, the moisture present in the air gets mixed with the water. The resulting mixture is then filtered to remove contaminants. Water evaporation has been found to be highly useful for this purpose, as it is one of the best ways to purify water.