Let’s study the separation of mixture by separating the mixture of salt, sand and ammonium chloride through the process of sublimation.
1. Common salt.
3. Ammonium chloride,
4. Filter paper,
6. China dish,
7. Tripod stand,
8. Wire gauge,
10. Glass rod,
12. Cotton plug.
1. Based on the properties of substances, they can be separated through a physical process, and one such process is known as sublimation.
2. Sublimation is the process of converting any solid substance to vapour form by heating.
3. For example, ammonium chloride is solid, and it will turn into vapour on heating.
4. Neither salt nor sand sublime on heating.
5. Therefore, if we heat these three substances (ammonium chloride, sand, and salt), ammonium chloride will vapourise, leaving behind salt and sand.
6. We can regain ammonium chloride in solid form by cooling.
NH4Cl(solid) → NH4Cl(vapour) → NH4Cl(solid)
7. We can separate sand and salt by dissolving them in water.
8. We know that salt dissolves in water while sand does not.
9. When we filter the mixture of salt, sand and water through filter paper, salt and water will pass through the filter paper, and sand will be collected on the filter paper.
10. Salt and water can be separated through evaporation.
11. Evaporation is the process of converting liquid or solid substances to vapour form.
12. When we heat the solution of salt and water, water will evaporate, and salt will be collected in the beaker.
13. We have obtained all the substances through the process of sublimation, filtration and evaporation.
1. SEPARATION OF AMMONIUM CHLORIDE
1. In a china dish, take the mixture of salt, sand and ammonium chloride and cover it with an inverted funnel.
2. Put some cotton over the inverted funnel.
3. Put the china dish over the tripod stand and give it heat.
4. You will see the ammonium chloride is undergoing sublimation and collecting on the inside walls of the inverted funnel.
5. Take out the funnel and scrap ammonium chloride from the walls.
6. The mixture of sand and salt is present in the china dish.
2. SEPARATION OF SAND
1. Add water to the mixture of salt and sand and stir it well.
2. Take a filter paper and give it the shape of a cone.
3. Filter the solution through the filter paper.
4. Salt is soluble in water, so it will filter out with water, and sand will remain on the surface of the filter paper.
1. Take the mixture of salt and water into a china dish.
2. Put the mixture over a flame.
3. Water will evaporate from the mixture leaving behind salt.
In this way, we have separated salt, sugar and ammonium chloride through the process of sublimation, filtration and evaporation. Hence we have successfully completed this science experiment of separation of mixture.
Q.1 What do you mean by volatile substance?
ANS. A substance which can easily convert into vapour at normal temperature is known as a volatile substance.
Q.2 What do you mean by non-volatile substance?
ANS. The substance which can not easily convert into vapour at normal temperature is known as a non-volatile substance.
Q.3 Define the solubility of a substance?
ANS. The tendency of a substance to get dissolve in liquid is known as the solubility of that substance.
Q.4 What do you mean by insoluble substance?
ANS. A substance which does not dissolve in a liquid is known as insoluble.
Q.5 What is the formula of common salt?
Q.6 What do you mean by sublimation?
ANS. Sublimation is the process of converting any solid substance to vapour form by heating.
Q.7 What do you mean by evaporation?
ANS. Evaporation is the process of converting liquid or solid substances to vapour form.
Q.8 How have you separated ammonium chloride from common salt and sand?
ANS. Through sublimation.
Q.9 How have you separated sand from salt?
ANS. Through filtration.
Q.10 How have you separated salt from water?
ANS. Through evaporation.
An Indian nuclear physicist, founding director, and professor of physics at the Tata Institute of Fundamental Research.