| What is Filtration used for? | This is used to separate an Insoluble Solid from a Liquid
Or in other words
If the product of a reaction is an insoluble solid, Filtration will separate it from a Liquid Reaction Mixture |
| Can it be used in Purification? | Yes. An example may be Solid impurities can be separated out from a reaction mixture using Filtration |
| Explain Filtration | 1. Put Filter paper into the top of a funnel, that's on top of a flask
2. Pour your mixture into it
3. The solution inside the Flask should be the liquid part, while the Filter paper should contain the solid residue. |
| What is Crystallisation used for? | This is used to separate soluble solid from a Solution |
| How do you do Crystallisation? | 1. Pour your solution into an Evaporating Basin and heat it up gently.
2. Some of the Solvent [Water usually] will evaporate making your Solution more concentrated.
3. When some of your solvent has evaported OR when you can see crystals start to form, remove the dish from the heat and allow it to cool.
4. The salt now will now form crystals as its insoluble in the cold, highly concentrated solution.
5. Filter the crystals out of the solution and let them rest in a warm place to dry. Alternatives could be a Drying Oven or a Desiccator [This contains Chemicals that remove water from the surroundings.] |
| How can you choose that right technique to separate the solid? | -Here is an Example. A mixture has X and Y. X is a liquid at room temperature [Melting point at 5, Boiling point at 60] and Y is a solid at room temperature [Melting point at 745 and boiling point at 1218] -Y has completely dissolved in X
-To get X, You will have to Distil it. Since its a liquid, and the boiling points are far apart. Distilling it will give you a Pure sample of X
-To get Y, you should use Crystallisation. Its a soluble solid.
[You could use the same technique as X, but there could be traces of X still there. This is just a better and reliable Technique] |
