Methods of Separation in Everyday Life – Short Answer Type Questions
Class 6
Science
Chapter 9
Methods of Separation in Everyday Life
CBSE Board Examinations
Topic-wise short answer practice for competitive revision and classroom tests
CBSE Board - Exam-wise guidance (Systematic)
- Very Short Answer Questions — 1 mark each (1–2 sentence answers)
- Short Answer Questions — 2–3 marks (brief explanations)
- Long Answer / Application — 5 marks (detailed explanation, steps)
- Practical/Application Questions — Describe separation methods and simple diagrams.
- Tip: Write steps clearly and mention the method name (e.g., Filtration, Evaporation).
Introduction: Why we need separation
1
What is a method of separation?
A method of separation is a technique used to separate different substances in a mixture based on their physical properties.
2
Give one everyday example of separation.
Separating tea leaves from tea using a strainer is an everyday example of separation.
3
Why do we separate mixtures?
We separate mixtures to obtain pure substances, remove impurities, or use components separately for different purposes.
4
Name two physical properties used for separation.
Particle size and magnetic properties are two physical properties often used for separation.
5
What is meant by a heterogeneous mixture?
A heterogeneous mixture has components that are not uniformly mixed and can often be separated by physical methods.
Handpicking and Winnowing
6
What is handpicking?
Handpicking is separating large or visible unwanted particles (like stones) from grains by picking them up manually.
7
When is handpicking used?
Handpicking is used when the components are large and easily seen, such as removing stones from pulses.
8
What is winnowing?
Winnowing is separating lighter husk from heavier grain using wind or by tossing in the air.
9
How does winnowing separate materials?
Winnowing uses difference in weight — lighter particles are blown away while heavier ones fall back.
10
Give one advantage of winnowing.
Winnowing is simple and does not require any equipment, making it useful in rural areas.
Sieving
11
What is sieving?
Sieving is passing a mixture through a sieve to separate particles of different sizes.
12
Where is sieving commonly used?
Sieving is used in kitchens to separate flour from lumps and in construction to separate aggregates by size.
13
What property is used in sieving?
Particle size is used; smaller particles pass through the sieve while larger particles are retained.
14
Can sieving separate dissolved substances?
No. Sieving separates only undissolved particles based on size, not dissolved substances.
15
Name an object used for sieving in the kitchen.
A flour sieve or a kitchen strainer is commonly used for sieving in the kitchen.
Sedimentation and Decantation
16
What is sedimentation?
Sedimentation is the process where heavier particles settle at the bottom of a liquid over time due to gravity.
17
What is decantation?
Decantation is pouring out the clear liquid from the top after sedimentation, leaving the solid sediment behind.
18
Give a common example of sedimentation and decantation.
Letting muddy water stand so the soil settles, then pouring out the clear water is sedimentation followed by decantation.
19
Why should decantation be done gently?
To avoid disturbing the sediment and mixing it back into the liquid, decantation must be done carefully.
20
Can decantation separate dissolved substances?
No. Decantation separates undissolved particles that settle; dissolved substances remain in the liquid.
Filtration
21
What is filtration?
Filtration is separating insoluble solids from liquids by passing the mixture through a filter paper or cloth which allows only the liquid to pass.
22
Name two examples of filtration at home.
Using a coffee filter to separate coffee grounds and using a sieve/strainer to remove solid bits from pulses are examples.
23
What is the solid left on the filter called?
The solid left on the filter is called the residue.
24
What is the liquid collected after filtration called?
The liquid that passes through the filter is called the filtrate.
25
Does filtration remove dissolved salts from water?
No. Filtration removes insoluble impurities; dissolved salts pass through the filter with the water.
Evaporation & Crystallisation
26
What is evaporation?
Evaporation is the process where a liquid changes into vapour on heating, leaving behind dissolved solids.
27
How is evaporation used to get salt from seawater?
Seawater is left in shallow pans; water evaporates in the sun and salt remains as crystals.
28
What is crystallisation?
Crystallisation is forming solid crystals from a solution when the solvent evaporates or when the solution is cooled.
29
Give one difference between evaporation and distillation.
Evaporation separates a solid dissolved in a liquid (no collection of vapour), while distillation collects and condenses vapour to get a pure liquid.
30
Why is evaporation useful in daily life?
Evaporation is used to dry clothes, concentrate solutions, and obtain salts from solutions.
Distillation
31
What is distillation?
Distillation is a method of separation where a liquid is boiled to produce vapour which is then condensed back to liquid to obtain a purified liquid.
32
When is distillation used at home?
Distillation is used in water purification plants and to obtain pure water (distilled water) in laboratories; at home, simple boiling is common, distillation is less common.
33
What property does distillation use to separate substances?
Distillation uses differences in boiling points of liquids to separate them.
34
What is simple distillation?
Simple distillation separates a liquid from a non-volatile solute or from another liquid with a very different boiling point.
35
Why is condensation important in distillation?
Condensation turns the vapour back into liquid so the purified liquid can be collected separately.
Magnetic Separation
36
What is magnetic separation?
Magnetic separation uses a magnet to separate magnetic materials from non-magnetic ones.
37
Give an example of magnetic separation.
Removing iron filings from sand using a magnet is an example of magnetic separation.
38
What property is used in magnetic separation?
Magnetic properties — whether a substance is attracted by a magnet — are used.
39
Is magnetic separation useful in recycling?
Yes. Magnetic separation helps separate ferrous metals from waste for recycling.
40
Can magnetic separation separate all metals?
No. It separates magnetic (ferrous) metals only; non-magnetic metals like aluminium are not attracted by magnets.
Other methods & Safety
41
What is chromatography (simple idea)?
Chromatography is a method to separate different coloured substances (like inks) based on how far they travel on a paper with a solvent.
42
Is chromatography part of Class 6 syllabus?
A simple introduction to chromatography (separating colours) may be shown as an advanced or demonstration activity.
43
What is a separating funnel used for?
A separating funnel separates two immiscible liquids (like oil and water) because they form separate layers.
44
What is meant by immiscible liquids?
Immiscible liquids do not mix and form separate layers, for example oil and water.
45
Why should you follow safety rules during experiments?
Safety rules prevent accidents, protect eyes and skin, and ensure experiments are carried out correctly and safely.
Revision & Application
46
How would you separate rice from pulses mixed together?
Use handpicking to remove rice grains or pulses (depending on size/colour) since they are large and visible.
47
How can you separate sugar dissolved in water?
Use evaporation to remove water and obtain sugar crystals, or use distillation to collect pure water separately.
48
How to remove mud from water for household use?
Let the water stand to allow sedimentation, decant the clear water, then filter to remove remaining particles.
49
Which method would you use to separate small iron pins from sand?
Use a magnet to attract and remove the iron pins (magnetic separation).
50
List the steps to obtain salt from salt solution.
Heat the solution to evaporate water; allow crystals to form; collect salt crystals (evaporation and crystallisation).
Short Answer Type Questions
CBSE Class 6 Science – Chapter Wise Study Materials Based on NCERT