NCERT Question-Answer Solution for Class 6 Science Chapter 9 – Methods of Separation in Everyday Life
Complete NCERT Question–Answer Set for Class 6 Science (Curiosity Textbook) – Chapter 9: Methods of Separation in Everyday Life
Class 6 Science NCERT Solution – Chapter 9: Methods of Separation in Everyday Life
Methods of Separation in Everyday Life – Full NCERT Question–Answer Set (CBSE Class 6 Science – Curiosity Book)
SECTION A – Multiple Choice Questions (MCQs)
1. What purpose does handpicking serve in the process of separation?
(i) Filtration
(ii) Sorting
(iii) Evaporation
(iv) Decantation
Answer: Sorting
Handpicking is used to manually sort out unwanted larger particles from a mixture.
2. Which of the following substances is commonly separated using the churning method?
(i) Oil from water
(ii) Sand from water
(iii) Cream from milk
(iv) Oxygen from air
Answer: Cream from milk
Churning separates lighter butter or cream from heavier buttermilk.
3. Which factor is essential for filtration?
(i) Apparatus size
(ii) Presence of air
(iii) Pore size
(iv) Temperature of the mixture
Answer: Pore size
Filtration works because pores allow liquid to pass and trap solids.
SECTION B – True or False
State True or False and correct the false statements.
4(i) Salt can be separated from salt solution by keeping it under the Sun.
Answer: True.
Evaporation removes water and leaves salt behind.
4(ii) Handpicking should be used only when the quantity of one component is less.
Answer: True.
It becomes difficult if impurities are large in amount.
4(iii) A mixture of puffed rice and rice grains can be separated by threshing.
Answer: False.
Correct statement: A mixture of puffed rice and rice grains can be separated by winnowing or handpicking, not threshing.
4(iv) A mixture of mustard oil and lemon water can be separated by decantation.
Answer: True.
Oil and water separate into layers.
4(v) Sieving is used to separate a mixture of rice flour and water.
Answer: False.
Correct statement: Rice flour dissolves partially and cannot be separated by sieving.
SECTION C – Match the Following
5. Match Column I with Column II
| Column I | Column II |
|---|---|
| (i) Gram flour mixed with black gram | (a) Handpicking |
| (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 |
Answer:
(i) Gram flour + black gram → Sieving
(ii) Chalk powder + water → Filtration
(iii) Corn + potatoes → Handpicking
(iv) Iron powder + sawdust → Magnetic separation
(v) Oil + water → Decantation
SECTION D – Short Answer Questions
6. In what situations would you use decantation instead of filtration?
Answer:
Decantation is used when
• solid particles settle at the bottom (sedimentation)
• the mixture has clear upper liquid that can be poured off
• mixtures like sand–water, tea without strainer, oil–water mixtures
It is useful when filtration is not possible but substances settle by gravity.
7. Can you relate the presence of nasal hair to any separation process?
Answer:
Yes. Nasal hair works like filtration.
It filters dust and small particles from the air we breathe and prevents them from entering the lungs.
8. During COVID-19, we wore masks. What material are they made of? What is their role?
Answer:
Masks are made of cotton, non-woven fabric, or multiple layered filter material.
Their role:
• to filter dust, droplets, microbes
• to act like a barrier filtration process
• to prevent harmful particles from entering the respiratory tract.
9. A mixture of potatoes, salt and sawdust is given. Write steps to separate all components.
Answer:
Answer:
Step 1 – Handpicking:
Remove the potatoes manually because they are the largest components.
Step 2 – Add water:
Salt dissolves in water.
Sawdust floats because it is lighter than water.
Step 3 – Skimming:
Remove the floating sawdust from the surface.
Step 4 – Decantation/Filtration:
Separate the water containing dissolved salt.
Step 5 – Evaporation:
Heat the salt solution to evaporate the water.
Salt crystals remain.
Final result:
• Potatoes → handpicking
• Sawdust → skimming
• Salt → evaporation
10. Intelligent Leela – Story Question
Choose correct options and give a title.
(a) Tick the most appropriate options (with answers):
- Before her father felt hungry / thirsty → thirsty
- She went to fetch some water / grains → water
- The water was fit / unfit for drinking → unfit
- She filtered / churned the muddy water → filtered
- She used a piece of paper / muslin cloth → muslin cloth
- She cooled / boiled the water → boiled
- After boiling, she filtered / churned it → filtered
- The water became fit / unfit for drinking → fit
(b) Suitable Title for the Paragraph
Answer:
“Leela’s Smart Way of Purifying Water”
(or)
“Clever Leela Purifies Water”
(or)
“Intelligent Leela Saves the Day”
(or)
“Leela’s Smart Way of Cleaning Water”
or
“How Leela Purified Water”
SECTION E – Higher Order Thinking Questions (HOTS)
11. Why do farmers not handpick husk from huge piles of grains?
Answer:
Because husk is extremely light and present in large quantity. Handpicking would take too long.
Winnowing is faster, easier, and highly effective.
12. Why does evaporation leave salt behind but not the water?
Answer:
Because water turns into vapour on heating or sunlight exposure, but salt does not evaporate and remains as solid crystals.
13. Why cannot filtration be used to separate salt from salt solution?
Answer:
Salt dissolves completely and passes through filter pores. Only insoluble impurities can be removed by filtration.
14. Why is a fishing net compared to filtration in the chapter?
Answer:
Because the mesh of the net allows water to pass through but traps larger objects (fish), similar to how filters trap particles and allow liquid to pass.
SECTION F – Long Answer Questions
15. Explain the differences between sedimentation, decantation and filtration with examples.
Answer:
Sedimentation: Heavy impurities settle down.
Example: Mud settles in muddy water.
Decantation: Clear water is poured out without disturbing sediment.
Example: Removing clean water from settled muddy water.
Filtration: Using filter paper or cloth to remove fine insoluble solids.
Example: Filtering tea leaves, filtering muddy water.
All three methods are used for solid–liquid mixtures.
16. Describe the process of obtaining common salt from seawater.
Answer:
Step 1: Seawater is poured into shallow pits.
Step 2: Sunlight heats the water causing evaporation.
Step 3: Water changes into vapour leaving salt behind.
Step 4: Salt is collected and purified further.
This uses evaporation as the main method.
17. Explain winnowing with the help of an example.
Answer:
Winnowing separates lighter and heavier components using wind.
Example: Separating wheat grains from husk.
Lighter husk is blown away while heavier grains fall straight to the ground.
SECTION G – Thinking Skill Questions
18. Which method will you use to separate:
• Iron nails
• Sand
• Stones
• Pepper
• Salt
• Water
Answer:
- Use a magnet → remove iron nails.
- Handpick → remove stones.
- Winnow → remove lighter pepper.
- Dissolve in water → salt dissolves; sand remains.
- Filter → remove sand.
- Evaporate → recover salt from solution.
SECTION H – Think and Start (From Text)
19. To remove any one of the components that is not useful, which method is used?
Answer:
Handpicking, sieving, winnowing, magnetic separation.
20. To separate two useful components, which method is used?
Answer:
Churning, sedimentation–decantation, filtration, evaporation.
SECTION I – Extra NCERT-based Short Questions
21. What is handpicking?
Answer:
Manual removal of impurities based on size, shape, or color.
22. Why is sieving useful?
Answer:
It separates particles of different sizes using a sieve.
23. What is the residue in filtration?
Answer:
Solid particles left on filter paper.
24. What is filtrate?
Answer:
Clear liquid that passes through filter paper.
25. What is magnetic separation?
Answer:
Using a magnet to remove magnetic substances like iron.
SECTION J – Extra Long Question (NCERT style)
26. With examples, explain any five methods of separation used in daily life.
Answer:
Handpicking – removing stones from rice.
Threshing – separating grains from stalks.
Winnowing – removing husk from wheat.
Filtration – filtering tea.
Evaporation – obtaining salt from seawater.
SECTION K – Match the Following (From Story)
27. Match Column I with Column II
| Column I | Column II |
|---|---|
| Ice cream | Solid |
| Steam | Gas |
| Rain | Condensed water |
| Water | Liquid |
| Fog | Tiny droplets |
Answer:
Ice cream → Solid
Steam → Gas
Rain → Condensed water
Water → Liquid
Fog → Tiny droplets