Ncert – class 6- science – Chapter 3: Separation of Substances 2 Welcome to your Ncert - class 6- science - Chapter 3: Separation of Substances 2 1. Threshing is a method of separation used to separate: tea leaves from tea stones from rice none of the above grain from stalk None 2. 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 3. A solution of sugar in which some more sugar could be dissolved without changing its temperature is called a/an : None of the above saturated solution unsaturated solution solid solution None 4. Winnowing is used for separation of: Homogeneous solid-liquid mixtures Heterogeneous solid-liquid mixtures Homogeneous solid-solid mixtures Heterogeneous solid-solid mixtures None 5. 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? Filtration Winnowing Sieving Threshing None 6. Sieving can be used only when the components of the mixture have: Different boiling points Different sizes Different melting points Different lustre None 7. A saturated solution of NaCl on heating : vapourises remains saturated. becomes unsaturated. becomes supersaturated. None 8. 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 : evaporation crystallization centrifugation sublimation None 9. Winnowing is used to separate: heavier and lighter particles of mixture. different sized particles in the mixture. a mixture of insoluble solid and liquid. None of these None 10. Sugar syrup, usually used to coat sweets with sugar, becomes hard when cooled. From this, we can conclude that sugar syrup is: an unsaturated solution not a solution none of these a saturated solution None 11. Which is the correct order to separate salt from a mixture of salt and sand? Filtration, Evaporation, Dissolving Dissolving, Filtration, Evaporation Evaporation, Dissolving, Filtration Filtration, Dissolving, Evaporation None 12. What would you observe when an aqueous sugar solution is heated to dryness? Sugar gets mixed with water and vaporize Sugar gets charged Sugar will be left behind in the container Water will vaporize 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. Winnowing is the process used to separate heavier and lighter components of a mixture by wind or by blowing air. All of the above. None 14. 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? Evaporation followed by condensation Filtration Sedimentation and decantation Condensation and crystallization None 15. In a saturated solution : Dissolved solute > > > >>> undissolved solute Dissolved solute and undissolved solutes are in equilibrium with each other None of these Dissolved solute < < < <<< undissolved solute None 16. 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? Suspension True solution Colloidal solution Saturated solution None 17. Which of the following process is used to obtain common salt from seawater? Filtration Sublimation Distillation Evaporation None 18. Saturated solution of salt on heating: vaporises becomes unsaturated becomes supersaturated remains saturated None 19. __________ is/are generally used for filtration. Cloth None of these Both A and B Filter paper None 20. The process of settling down of heavier, insoluble particles in an undisturbed mixture solution is called: sedimentation centrifugation decantation 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.