CHAPTER 3
Practice Set 3
Let’s Separate the Components
Grade 6 Science • Maharashtra State Board • 30 Marks
Q.1 (A) Choose the correct option.
4 Marks
(1) The components of which mixture can be easily picked out and separated?
(2) What remains on a sieve when flour is sieved?
(3) Why does butter float on buttermilk?
(4) Which institute created a filtering curtain from the ash of burnt crop straw?
Q.1 (B) Complete the analogies.
4 Marks
(1) Winnowing : Grains and chaff :: Sieving :
(2) Filter paper : Muddy water :: Churner :
(3) Sunlight : Evaporation :: Wind :
(4) Iron : Magnetic substance :: Sawdust :
Q.2 State whether true or false. Correct the false statement.
3 Marks
(1) The components of every mixture can be separated easily by hand.
(2) Particles larger than the holes of a sieve remain on its mesh.
(3) Oil and water form one uniform layer when mixed.
Q.3 Identify the method suitable for each mixture.
4 Marks
| Mixture | Suitable Method |
|---|---|
| (1) Grain and dried leaves | ________________ |
| (2) Mud and water | ________________ |
| (3) Salt and water | ________________ |
| (4) Iron pieces and non-magnetic waste | ________________ |
Q.4 Answer in one or two sentences.
3 Marks
(1) How are suitable methods planned for separating the components of a mixture?
(2) What happens to the smaller and larger particles when a mixture is passed through a sieve?
(3) What happens when roasted peanuts or chickpeas are rubbed and then blown upon?
Q.5 Answer the following in detail.
6 Marks
(1) Sand and gravel have mixed at a construction site. Explain how they can be separated.
(2) Explain how a sieve separates coarse particles from fine particles.
(3) Write the steps for cleaning muddy water using alum, sedimentation and decantation.
Q.6 Read the situations and answer.
4 Marks
(1) A student pours buttermilk through filter paper. What will happen to the solid particles and the liquid? Name the method.
(2) A farmer has a large quantity of grain mixed with chaff. How can a machine complete the work faster than manual winnowing?
Q.7 Answer the questions about Dr. Uddhab Bharali.
2 Marks
(1) Why did Dr. Bharali develop his own plastic-bag-making machine instead of purchasing a foreign machine?
(2) Name any two notable machines or tools invented by Dr. Bharali.
Q.8 Complete the concept map.
4 Marks
Difference in shape and colour
↓
Method: __________________
Difference in weight
↓
Method: __________________
Difference in particle size
↓
Method: __________________
Magnetic property
↓
Method: __________________
CHAPTER 3
Practice Set 3 – Solutions
Let’s Separate the Components
Q.1 (A) Choose the correct option.
(1) Mixture whose components can be easily picked out
Answer: (c) Bhel
(2) Particles remaining on the sieve
Answer: (b) Coarse bran particles
(3) Reason butter floats on buttermilk
Answer: (c) It is fatty and light
(4) Institute that created the filtering curtain
Answer: (a) Energy and Resources Institute
Q.1 (B) Complete the analogies.
(1) Winnowing : Grains and chaff :: Sieving : ______
Answer: Flour and bran
(2) Filter paper : Muddy water :: Churner : ______
Answer: Curd
(3) Sunlight : Evaporation :: Wind : ______
Answer: Winnowing
(4) Iron : Magnetic substance :: Sawdust : ______
Answer: Non-magnetic substance
Q.2 State whether true or false. Correct the false statement.
(1) The components of every mixture can be separated easily by hand.
False.
The components of some mixtures can be easily picked out, but many mixtures require particular methods of separation.
(2) Particles larger than the holes of a sieve remain on its mesh.
True.
(3) Oil and water form one uniform layer when mixed.
False.
Oil and water do not mix uniformly. They form two separate layers.
Q.3 Identify the method suitable for each mixture.
| Mixture | Suitable Method |
|---|---|
| (1) Grain and dried leaves | Winnowing |
| (2) Mud and water | Sedimentation followed by decantation |
| (3) Salt and water | Evaporation |
| (4) Iron pieces and non-magnetic waste | Magnetic separation |
Q.4 Answer in one or two sentences.
(1) How are suitable methods planned for separating the components of a mixture?
Answer: The differences between the properties of the mixed substances are identified. A method that uses those differences is then selected.
(2) What happens to smaller and larger particles during sieving?
Answer: Particles smaller than the holes pass through the sieve. Particles larger than the holes remain on its mesh.
(3) What happens when roasted peanuts or chickpeas are rubbed and blown upon?
Answer: Their light coverings are blown away, while the heavier, clean peanuts or chickpeas remain on the palm.
Q.5 Answer the following in detail.
(1) Sand and gravel have mixed at a construction site. Explain how they can be separated.
Answer: Sand and gravel differ in particle size. The mixture should be passed through a suitable sieve. The smaller sand particles will pass through its holes, while the larger pieces of gravel will remain on the sieve.
(2) Explain how a sieve separates coarse particles from fine particles.
Answer: A sieve contains holes of a particular size. When a mixture is placed on it, particles smaller than the holes fall through. Coarse particles larger than the holes remain on the sieve mesh.
(3) Write the steps for cleaning muddy water using alum, sedimentation and decantation.
Answer:
- Partially dip a piece of alum in the muddy water.
- Swirl it four to five times so that a small amount of alum dissolves.
- The alum particles stick to the soil particles and make them heavier.
- Leave the water undisturbed so that the soil settles at the bottom.
- Carefully pour the clearer water into another vessel without disturbing the settled soil.
Q.6 Read the situations and answer.
(1) A student pours buttermilk through filter paper. What will happen?
Answer: The liquid will pass through the microscopic pores of the filter paper, while the insoluble solid particles will remain on it. This method is called filtration.
(2) How can a machine complete winnowing faster?
Answer: A large fan can create a strong flow of air. When the mixture is dropped, heavy grains fall down while the lighter chaff is carried away. The strong airflow separates a large quantity in less time.
Q.7 Answer the questions about Dr. Uddhab Bharali.
(1) Why did Dr. Bharali develop his own plastic-bag-making machine?
Answer: His family was facing a financial crisis due to loans. Instead of buying a foreign machine costing ₹5.5 lakh, he developed his own machine for ₹60,000.
(2) Name any two notable machines or tools invented by Dr. Bharali.
Answer:
1. A machine that peels fruits and separates seeds.
2. A tool that extracts pomegranate seeds.
1. A machine that peels fruits and separates seeds.
2. A tool that extracts pomegranate seeds.
Q.8 Complete the concept map.
Difference in shape and colour
↓
Handpicking
Difference in weight
↓
Winnowing
Difference in particle size
↓
Sieving
Magnetic property
↓
Magnetic Separation