Chapter 9 Methods of Separation in Everyday Life Class 6 Science Curiosity NCERT Solutions
Chapter 9 Methods of Separation in Everyday Life NCERT Solutions Class 6 Science
Question 1. As a small amount of puffed rice is mixed with chana dal? Can you think of separating the mixture by any method other than handpicking?
Answer
The mixture of rice with chana dal can be separated by sieving or by using soop(bamboo tray) other than handpicking.
Question 2. Valli is unable to separate husk from rice in a closed room. How can you help her?
Answer
Valli can use a fan to separate husk from rice.
The process of winnowing help Valli in separating husk from rice as husk being lighter will carried away by the air and grain being heavier will fall down.
Question 3. Have you ever observed sieves being used at construction sites to separate pebbles and stones from the sand?
Answer
Yes, I have observed using large sieve to separate pebbles and stones from the sand.
Question 4. Have you ever observed white patches on the dark coloured clothes you wear during hot summers? How are these patches formed?
Answer
The white patches formed on the dark coloured clothes during summer are formed due to evaporation of sweat due to heat leaving behind salts on the clothes.
Question 5. Observe the figure. Does it answer the question? Can you name the process involved?
Answer
Yes, it answers the question. The process involved in the above picture is condensation.
Question 6. In the chapter ‘Materials Around Us’, you have studied that oil does not mix with water and forms a separate layer when left undisturbed for some time. Which method of separation would you use to separate oil and water?
Answer
The process we use to separate oil and water is decantation. In this process, the water (liquid) is removed by tilting the vessel.
Let us enhance our learning
1. What purpose does handpicking serve in the process of separation?
(i) Filtration
(ii) Sorting
(iii) Evaporation
(iv) Decantation
Answer
(ii) Sorting
2. Which of the following substances are commonly separated using the churning method?
(i) Oil from water
(ii) Sand from water
(iii) Cream from milk
(iv) Oxygen from air
Answer
(iii) Cream from milk
3. Which factor is usually essential for the filtration?
(i) Apparatus size
(ii) Presence of air
(iii) Pore size
(iv) Temperature of the mixture
Answer
(iii) Pore size
4. State with reason(s) whether the following statements are True [T] or False [F]. Also, correct the False statement(s).
(i) Salt can be separated from salt solution by keeping it under the Sun. [ ]
(ii) Handpicking should be used only when the quantity of one component is less. [ ]
(iii) A mixture of puffed rice and rice grains can be separated by threshing. [ ]
(iv) A mixture of mustard oil and lemon water can be separated by decantation. [ ]
(v) Sieving is used to separate a mixture of rice flour and water. [ ]
Answer
(i) Salt can be separated from salt solution by keeping it under the Sun. True [T]
(ii) Handpicking should be used only when the quantity of one component is less. True [T]
(iii) A mixture of puffed rice and rice grains can be separated by threshing. False [F]
Correct Statement: A mixture of puffed rice and rice can be separated by winnowing as puffed rice is lighter than rice grain.
(iv) A mixture of mustard oil and lemon water can be separated by decantation. True [T]
(v) Sieving is used to separate a mixture of rice flour and water. False [F]
Correct Statement: To separate rice flour and water, evaporation or filtration is used.
5. Match the mixtures in Column I with their method of separation in Column II.
Answer
| Column I | Column II |
| (i) Gram flour mixed with black gram | (d) Sieving |
| (ii) Chalk powder mixed with water | (e) Filtration |
| (iii) Corn mixed with potatoes | (a) Handpicking |
| (iv) Iron powder mixed with sawdust | (b) Magnetic separation |
| (v) Oil mixed with water. | (c) Decantation |
6. In what situations would you use decantation instead of filtration to separate solids from liquids?
Answer
Decantation method can be used other than filtration to separate solids from liquids. This method is used when the solid particles are heavy and settle down at the bottom of the container. It allows the clear liquid to be poured off without disturbing the solid sediment.
For example separating sand from water.
7. Can you relate the presence of nasal hair to any separation process?
Answer
Yes, the presence of nasal hair can be compared to the process of filtration. Filtration removes unwanted impurities from liquids and gases. Similarly, nasal hair filters out dust particles, pollen, and other foreign particles from the air we breathe. This prevents them from entering the respiratory tract.
8. During the COVID-19 pandemic, all of us wore masks. Generally, what material are they made of? What is the role of these masks?
Answer
Masks are generally made of cotton fabric, polyester, and polypropylene. They not only prevent dust particles present in the air from entering the nasal cavity but also act as a barrier, blocking bacteria, viruses, and other pathogens.
9. A mixture containing potatoes, salt and sawdust has been given to you. Outline a stepwise procedure for separating each component from this mixture.
Answer
Stepwise procedure for separating each component:
- Separate the potatoes from the mixture by handpicking.
- Add water to the remaining mixture of salt and sawdust, which will dissolve the salt.
- Filter the sawdust from the salt solution using filter paper.
- Evaporate the water from the salt solution to obtain the salt.
10. Read the following story titled ‘Intelligent Leela’ and tick the most appropriate options. Provide a suitable title of your choice for the paragraph.
Leela was working in the farm with her father when she realised that they left their drinking water at home. Before her father felt thirsty/hungry, she went to the nearby pond to fetch some water/grains. After obtaining some water in the container, she noticed that the water was muddy and fit/unfit for drinking. To purify the water, she kept it for some time and then she filtered/churned the muddy water using a piece of paper/muslin cloth. Leela, then, cooled/boiled the water for about 10 minutes in a covered pan. After cooling/boiling, she filtered/churned it again and made it fit/unfit for drinking. She served this water to her father while having food, who blessed her and appreciated her efforts.
Answer
Title: Leela purify water for her father
Leela was working in the farm with her father when she realised that they left their drinking water at home. Before her father felt thirsty, she went to the nearby pond to fetch some water. After obtaining some water in the container, she noticed that the water was muddy and unfit for drinking. To purify the water, she kept it for some time and then she filtered the muddy water using a piece of paper/muslin cloth. Leela, then, boiled the water for about 10 minutes in a covered pan. After cooling, she filtered it again and made it fit for drinking. She served this water to her father while having food, who blessed her and appreciated her efforts.