Ncert – class 6- science – Chapter 3: Separation of Substances 2 Welcome to your Ncert - class 6- science - Chapter 3: Separation of Substances 2 1. In a saturated solution : Dissolved solute and undissolved solutes are in equilibrium with each other Dissolved solute < < < <<< undissolved solute None of these Dissolved solute > > > >>> undissolved solute None 2. Sieving can be used only when the components of the mixture have: Different sizes Different boiling points Different melting points Different lustre None 3. Sugar syrup, usually used to coat sweets with sugar, becomes hard when cooled. From this, we can conclude that sugar syrup is: a saturated solution none of these an unsaturated solution not a solution None 4. Threshing is a method of separation used to separate: grain from stalk none of the above tea leaves from tea stones from rice None 5. To separate a mixture in which the solid is insoluble in the liquid, and is also heavier than the liquid, which of the following methods of separation are most suited? Sedimentation and decantation Filtration Evaporation followed by condensation Condensation and crystallization None 6. What would you observe when an aqueous sugar solution is heated to dryness? Sugar gets mixed with water and vaporize Water will vaporize Sugar will be left behind in the container Sugar gets charged None 7. A solution of sugar in which some more sugar could be dissolved without changing its temperature is called a/an : saturated solution None of the above solid solution unsaturated solution None 8. Saturated solution of salt on heating: vaporises becomes supersaturated remains saturated becomes unsaturated None 9. Winnowing is used for separation of: Heterogeneous solid-solid mixtures Homogeneous solid-solid mixtures Heterogeneous solid-liquid mixtures Homogeneous solid-liquid mixtures None 10. Rakesh was preparing a true solution of sugar in water in a beaker. By chance, he added sugar in excess. He kept stirring the solution for sometime but the sugar settled down in the beaker. He filtered the solution. What will be the nature of the filtrate? True solution Suspension Saturated solution Colloidal solution None 11. Winnowing is used to separate: None of these a mixture of insoluble solid and liquid. different sized particles in the mixture. heavier and lighter particles of mixture. None 12. A saturated solution of NaCl on heating : becomes supersaturated. remains saturated. becomes unsaturated. vapourises None 13. Which of the following represents correct statement(s)? In winnowing, the stalks are beaten to free the grain seeds. Winnowing is the process that is used to separate grain from stalks. All of the above. Winnowing is the process used to separate heavier and lighter components of a mixture by wind or by blowing air. None 14. Which is the correct order to separate salt from a mixture of salt and sand? Dissolving, Filtration, Evaporation Filtration, Dissolving, Evaporation Filtration, Evaporation, Dissolving Evaporation, Dissolving, Filtration None 15. Salt can be recovered from its solution by evaporation. Another technique which can be used for the separation of a salt from its solution is : centrifugation sublimation crystallization evaporation None 16. __________ is/are generally used for filtration. None of these Cloth Filter paper Both A and B None 17. At a particular temperature, a solution that has dissolved as much solute as it is capable of dissolving is said to be a: unsaturated solution saturated solution both A and B none of the above None 18. A mixture contains two solids A and B. Solid A is light in weight while solid B is very heavy. Their sizes are almost the same. Here, A is the unwanted component. To get pure solid B, which separation method would you suggest? Threshing Sieving Filtration Winnowing None 19. The process of settling down of heavier, insoluble particles in an undisturbed mixture solution is called: sedimentation centrifugation decantation filtration None 20. Which of the following process is used to obtain common salt from seawater? Distillation Evaporation Sublimation Filtration None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.