Methods+of+separation

Introduction
In the world of science, there are numerous methods of separation for different purposes. These methods are actually daily occurrence around the world, and sometimes are vital to our lives too, like the water cycle, involving evaporation. Some of them are discovered long time ago, while some came to existence with technology. In this article, I will discuss three different methods of separation.

Evaporation to dryness
=== So, what is evaporation? It is the process whereby water (liquid state) turns into water vapour (gaseous state). So, why can this be considered a separation technique? Imagine this scenario, whereby you have sea water. You want to get only the salt from the sea water, but it has long dissolved in water. So in this case, you have to evaporate the water away to obtain the salt. To do this, firstly, put the sample of seawater that you want to obtain salt from in a evaporating dish. Then, heat it with a bunsen burner below it. Make sure the flame is blue, as it will be hotter. Finally, wait until all the water has evaporated, and thus salt will be left on the dish. That is evaporation to dryness. ===

Distillation
Secondly, we come to distillation. Distillation is a process whereby the mixture is heated, and the hot vapours are collected, thus obtaining a pure sample. For the instance of sea water again, let's say you want pure water from it. Firstly, put the sea water into a flask, and connect the flask to a condensor. Also, put a rubber on top to stop vapours from escaping too. Then, at the other end of the condensor, place a beaker to collect the liquid. Then, heat the flask with a bunsen burner until all of the water evaporated. The water will turn to water vapour, which in turn will condense inside the condensor. The condensed pure water will then flow down the condensor and drip into the beaker. Thus, a pure sample of water is obtained.

For the case of fractional distillation, there must be a fractionating column connected to the top of the flask, and the thermometer connected at the top of the fractionating column. Finally, the condensor must be connected to the fractionating column. Fractional distillation is to seperate a mixture of liquids. So, in this case, firstly, we need to know the boiling points of the different liquids in the mixture. For instance, mixture A is made up of liquid A and liquid B. Liquid A's boiling point is 80 degree celsius, while Liquid B's boiling point is 100 degree celsius. So, when heated, let the liquid keep dripping to the beaker, until the thermometer reaches 100 degree celsius. As liquid B would boil at only 100 degree celsius, all the liquid in the beaker now is liquid A, as only liquid A boils below 100 degree celsius int this case.

Filtration
Lastly, filtration. Filtration is a process whereby a mixture of solids or solid and liquid is seperated, via a filter paper. As filter papers have small pores that are small enough to not let solids pass through, only liquids pass through the filter paper, thus leaving the solids on the filter paper. The liquids,in this case, would be known as the "filtrate", while the solids would be the "residue". This method of separation allows the user to retain back all the components of the mixture, unlike some others, if used correctly.

Although it is possible just to use the filter paper for filtration, it is not recommended, as the liquid that might be needed will be wasted. You will need a container with a small opening (e.g. flask, test tube...etc.) too. To set-up, firstly fold the filter paper in half. Then, fold it in equal halves again. Now, you will get a quadrant. Open the top part (the arc) in such a way that you get a cone, and place it on the opening of the flask. Now, just finish up by pouring the mixture carefully on the filter paper, and wait for all the liquid to be filtered through.

Source(s)

 * Wikipedia
 * Notes

Disclaimer: This is not copy and pasted.

Reflection
I chose to do this article about methods of separation, as at first, as a small form of revision, I looked through my file and found some methods of filtration, thus I decided to make one article about it. Half-way through though, I realized I might have forgotten something, so I searched some up on wikipedia too. These methods are few of the important discoveries man had made, that shaped the world we are in, for instance in the case of distillation. It is now a method that is widely used around the world for making distilled water, which is sold around the world.