Separation of substances Worksheet-10

Separation of substances Worksheet-10

Multiple-Choice Question:

21. Which process is used to separate pieces of chaff from the grain?

(A) Threshing      (B) Winnowing    (C) Sieving

22. _______ is lighter than the ________.

(A) Chaff, grain    (B) Grain, chaff    (C) Grain, seed

23. In winnowing process, the __________ falls vertically.

(A) Chaff              (B) Grain              (C) Fodder

24. In winnowing process, _______ is carried away by the wind and it forms a separate heap.

(A) Chaff              (B) Grain              (C) Fodder

25. Which factor plays an important role in the process of winnowing?

(A) Direction of water                     (B) Direction of wind

(C) Temperature and pressure

26. By which process the impurities like small stones can be separated from the wheat?

(A) Filtration       (B) Decantation  (C) Hand-picking

27. Hand-picking method is preferred when:

(A) Quality of mixture is good.

(B) The required substance is present in smaller quantity.

(C) The size, shape or colour of the unwanted substance is different from that of the useful one.

28. By which process can we separate the components of a mixture of different size?

(A) Winnowing   (B) Sieving           (C) Hand-picking

29. Following is not the threshing method:

(A) Manual threshing                      (B) Mixed threshing

(C) Combined harvesting

30. By which method can we separate the wheat bran from flour?

(A) Winnowing   (B) Sieving           (C) Hand-picking

31. ______ is a very rich source of fibre.

(A) Wheat flour   (B) Wheat bran   (C) Wheat seed

32. The visible impurities can be removed by _______ process.

(A) Winnowing   (B) Sieving           (C) Hand-picking

33. At construction sites, the pebbles and stones from sand can be separated by the process of _______.

(A) Winnowing   (B) Sieving           (C) Hand-picking

34. Which of the following statement is TRUE for a saturated solution?

(A) The solution in which only solid dissolves

(B) The solution in which no more of solute can dissolve

(C) The solution in which no more of solvent can dissolve

35. By which method can we obtain the insoluble solids suspended in a liquid?

(A) Sedimentation (B) Filtration     (C) Absorption

36. We can pour out the clear upper liquid from the solution by _________ process.

(A) Sedimentation (B) Decantation (C) Filtration

Answer key:

21. (B)
22. (A)
23. (B)
24. (A)
25. (B)
26. (C)
27. (C)
28. (B)
29. (B)
30. (B)
31. (B)
32. (B)
33. (B)
34. (B)
35. (A)
36. (B)