0
0
1. The process by which butter can be separated from milk is ____.
a.) Sedimentation
b.) Decantation
c.) Filtration
d.) Churning
Answer – (d.) Churning
Explanation – Churning is the process of continuously moving milk or curd with skimmers to produce butter.
2. Which of the following processes can be used to separate a liquid from an insoluble solid?
a.) Evaporation
b.) Sedimentation
c.) Distillation
d.) Filtration
Answer – (d.) Filtration
Explanation – Filtration is the process of separating suspended solid matter from a liquid by passing it through the pores of a membrane known as a filter. For example, tea leaves are separated from tea by filtration.
3. Choose the incorrect statement from the following.
a.) Decantation is the process of transferring the clear liquid without disturbing the sediments.
b.) Decantation is the process of separating an insoluble solid from a liquid using filter paper.
c.) Decantation is the process of settling down heavier, insoluble particles from a mixture
d.) Decantation is the process in which solid changes directly into a vapour state.
Answer – (a.) Decantation is the process of transferring the clear liquid without disturbing the sediments.
Explanation – The decantation process is carried out just after sedimentation.
4. Which of the following processes can be used to separate impurities from wheat?
a.) Magnetic separation
b.) Winnowing
c.) Handpicking
d.) Threshing
Answer – (c.) Handpicking
Explanation – Handpicking is a technique that separates undesirable substances such as small pieces from wheat, rice, and pulses. Stone fragments from grains are picked up by hand and discarded.
5. Which of the following processes is used to separate grains from stalks?
a.) Threshing
b.) Winnowing
c.) Handpicking
d.) All of the above
Answer – (a.) Threshing
Explanation – Threshing is the separation of grain from the stalk on which it grows as well as the chaff or unit that covers it. The edible portion of the crop is loosened during the process, but not the fibre portion.
6. Salt is obtained from seawater by the process of ____.
a.) Sedimentation
b.) Decantation
c.) Evaporation
d.) Distillation
Answer – (c.) Evaporation
Explanation – A large amount of seawater is stored in a sand dig with a large surface area and allowed to evaporate by absorbing solar energy. The water evaporates, but the sea salts remain in the dig.
7. Which of the following processes involves leaving the insoluble mixture to stand for some time and then separating the impurities?
a.) Sedimentation
b.) Decantation
c.) Filtration
d.) Evaporation
Answer – (a.) Sedimentation and (b.) Decantation
Explanation – Sedimentation is the process of separating insoluble substances that are heavier than liquid by allowing them to settle naturally due to gravity. The clear upper liquid is poured out of the container without disturbing the sediment during decantation.
8. In the process of distillation, evaporation is followed by ____.
a.) Filtration
b.) Sublimation
c.) Condensation
d.) None of the above
Answer – (c.) Condensation
Explanation – Distillation is the process of separating a liquid from a mixture through evaporation and condensation.
9. Which method can be used to separate iron and copper?
a.) Crystallisation
b.) Sublimation
c.) Evaporation
d.) Magnetic separation
Answer – (d.) Magnetic separation
Explanation – Both iron and copper are metals, but iron can be attracted by magnets, and copper cannot. Hence, they can be separated by magnetic separation.
10. Which of the following processes is done after harvesting?
a.) Winnowing
b.) Threshing
c.) Reaping
d.) Cutting
Answer – (b.) Threshing
Explanation – Reaping and cutting is done before harvesting. The first process after harvesting is threshing which is beating out the grain from the chaff. Winnowing separates chaff and hay from the grain after threshing.
11. The separation of heavier, insoluble impurities in an undisturbed mixture solution is known as ____.
a.) Sedimentation
b.) Decantation
c.) Evaporation
d.) Distillation
Answer – (a.) Sedimentation
Explanation – The mixture of liquid and insoluble solid is placed in a container during sedimentation. Gravity causes the heavier solid particles to settle at the bottom of the container. These solid particles are referred to as sediment.
12. The process of conversion of vapour into liquid is called ____.
a.) Evaporation
b.) Crystallisation
c.) Sublimation
d.) Condensation
Answer – (d.) Condensation
Explanation – Condensation occurs in one of two ways: The air is either cooled to its dew point or becomes so saturated with water vapour that it cannot hold any more water.
13. Chalk powder can be separated from water by _____.
a.) Sedimentation
b.) Decantation
c.) Condensation
d.) Filtration
Answer – (d.) Filtration
Explanation – Chalk powder does not dissolve in water and cannot pass through filter paper. Thus, the mixture can easily be separated by the filtration process.
14. Components of a mixture separated by sieving are done based on differences in their:
a.) Weight
b.) Colour
c.) Shape
d.) Size
Answer – (d.) Size
Explanation – The sieving method is used to separate solid constituents of a mixture that vary in size.
15. The process of ____ separates the cotton fibre from cotton seeds.
a.) Threshing
b.) Sieving
c.) Ginning
d.) Boiling
Answer – (c.) Ginning
Explanation – The process of separating cotton fibres from cotton seeds or lint is known as ginning. It also helps to remove impurities like dust, small stones, and wood particles.
16. The process of separating camphor from sand is ____.
a.) Sublimation
b.) Crystallisation
c.) Evaporation
d.) Distillation
Answer – (a.) Sublimation
Explanation – We can separate camphor from sand by slowly heating the mixture. The camphor vapours are then collected and cooled. The solid camphor will crystallise. This is also known as sublimation.
17. Which of the following processes can be used to separate a mixture of sand and salt?
a.) Sedimentation and decantation
b.) Filtration
c.) Evaporation
d.) All of the above
Answer – (d.) All of the above
Explanation – Sand and salt are mixed with water, the salt dissolves in the water, and the sand can be separated by sedimentation, decantation, and filtration. The salt can then be separated using evaporation.
18. The process by which pure salt can be obtained from impure salt is:
a.) Crystallisation
b.) Sublimation
c.) Evaporation
d.) Sieving
Answer – (a.) Crystallisation
Explanation – The physical transformation of a liquid, solution, or gas to a crystal, which is solid with an ordered internal arrangement of molecules, ions, or atoms, is known as crystallisation.
19. The process of conversion of liquid into vapour is called ____.
a.) Evaporation
b.) Condensation
c.) Heating
d.) All of the above
Answer – (a.) Evaporation
Explanation – Evaporation takes place when liquids are heated, and then they get converted into vapours.
20. The process in which a mixture of heavier particles and lighter particles are separated by the wind is ____.
a.) Threshing
b.) Reaping
c.) Harvesting
d.) Winnowing
Answer – (d.) Winnowing
Explanation – This method is used to separate the husk from heavy grain seeds.
