Which separation technique will you apply for the separation of the following?

(a) Sodium chloride from its solution in water


(b) Ammonium chloride from a mixture containing sodium chloride and ammonium chloride


(c) Small pieces of metal in the engine oil of a car.


(d) Different pigments from an extract of flower petals.


(e) Butter from curd.


(f) Oil from water.


(g) Tea leaves from tea.


(h) Iron pins from sand.


(i) Wheat grains from husk.


(j) Fine mud particles suspended in water.

(a) Sodium chloride can be separated from its solution in water by the process of Evaporation. This solution is boiled or evaporated. After evaporation sodium chloride will be left behind.

(b) Ammonium chloride can be separated from a mixture containing sodium chloride and ammonium chloride by the process of ‘Sublimation’. On heating this mixture, ammonium chloride changes directly from solid to gaseous state leaving behind sodium chloride. During this process, the solids form of ammonium chloride can be collected on the sides of the funnel.


(c) Small pieces of metal in the engine oil of a car can be separated by the process of ‘Filtration’.


(d) Different pigments from an extract of flower petals can be separated by the process of ‘Chromatography’. Chromatography is the technique which is used for separation of those solutes that dissolve in the same solvent.


(e) Butter can be separated from curd by the process of Centrifugation. The principle behind this process is that the denser particles are forced to the bottom and the lighter particles stay at the top when spun rapidly.


(f) Oil can be separated from water by using ‘Separating funnel’. Mixture of oil and water are poured in the funnel and are allowed to stand undisturbed for sometime. This results in the formation of separate layers of water and oil.


(g) Tea leaves from tea can be separated by filtration.


(h) Iron pins can be separated from sand by using a magnet.


(i) Wheat grains can be separated from husk by Winnowing. It is a very simple process in which the wheat grains are thrown into the air, so that the wind blows away the lighter husk.


(j) Mud particles suspended in water can be removed by decantation and filtration.


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