(A)describe any three properties of colloid (B) one would need to separate the following mixture: (a) Mercury and water (b) potassium chloride and ammonium chloride (c)common salt, water and sand (d) kerosene oil, water and sand
Answers
Explanation:
(a) Fog (b) Cheese (c) Coloured gemstone. Ans. ... Describe any three properties of colloid. Ans. ... Pour the mixture of kerosene oil and water in separating funnel as shown in figure.
Answer:
It is a heterogenous mixture. Size of particles is too small to be seen by naked eye. They scatter light passing through them making its path visible. They do not settle down when left undisturbed.
Explanation:
a) Mercury and water are separated by decantation by using separating funnel as the separation of two immiscible liquids by a separating funnel depends on the difference in their densities. Mercury is heavier than water therefore, forms the lower layer and separated from water. (b) Potassium chloride and ammonium chloride are separated by sublimation method because ammonium chloride being a sublimate, sublimes leaving behind the potassium chloride. Sublimation is the process in which a solid changes directly into vapours on heating and vapours change into solid on cooling without going in liquid state. (b) Potassium chloride and ammonium chloride are separated by sublimation method because ammonium chloride being a sublimate, sublimes leaving behind the potassium chloride. Sublimation is the process in which a solid changes directly into vapours on heating and vapours change into solid on cooling without going in liquid state. Separation of potassium chloride and ammonium chloride by sublimation (c) Common salt, water and sand are separated by (i) Decantation (or filtration) process is used to separate sand from common salt solution in water because common salt is soluble in water whereas sand is insoluble in water. Therefore, by filtration, sand will be separated as insoluble substance as residue and filtrate will be common salt solution in water. (ii) Evaporation process is used to separate common salt from water. Water evaporates and common salt remains as residue. (d) (i) Decantation by using separating funnel is used to separate kerosene nil from salt solution in water as they form separate layers (salt is soluble in water). (ii) Evaporation is used to separate salt from water.