CHAPTER 3
Practice Set 2
Let’s Separate the Components
Grade 6 Science • Maharashtra State Board • 30 Marks
Q.1 (A) Choose the correct option.
4 Marks
(1) Which method is suitable for removing chillies from vegetables?
(2) Which substance is used to make soil particles in muddy water settle faster?
(3) In which place is seawater collected for obtaining salt?
(4) Which group contains only magnetic substances?
Q.1 (B) Name the method of separation.
4 Marks
(1) Carefully pouring the clear liquid into another vessel after the solid particles have settled.
(2) Separating coarse particles from flour using a fine mesh.
(3) Separating cream from milk in a large dairy using a rapidly rotating machine.
(4) Removing small pieces of trash from grains by observing their shape and colour.
Q.2 Find the odd one out and state the reason.
3 Marks
(1) Iron, cobalt, nickel, chaff
(2) Strainer, fine sieve, filter paper, magnet
(3) Maharashtra, Gujarat, Tamil Nadu, Assam
Q.3 Complete the following processes.
3 Marks
Muddy water kept undisturbed
→
→
Soil collects at the bottom
Curd is churned
→
→
A lump of butter is formed
Seawater kept in sunlight
→
→
Salt remains behind
Q.4 Distinguish between the following.
4 Marks
| Comparison | First Method | Second Method |
|---|---|---|
| (1) Sedimentation and Decantation | Meaning of sedimentation | Meaning of decantation |
| (2) Handpicking and Winnowing | Property used in handpicking | Property used in winnowing |
Q.5 Answer the following.
6 Marks
(1) Explain how grains and chaff are separated by dropping their mixture from a height.
(2) Describe the process of sedimentation and decantation using muddy water.
(3) How is salt obtained from seawater in salt pans?
Q.6 Answer the following activity-based questions.
4 Marks
(1) A bottle contains equal quantities of oil and water. What will be observed after the bottle is left undisturbed? How can the two liquids be separated using a container with a small hole at its bottom?
(2) Srushti keeps a saucer containing salt solution in the shade, Yash keeps it in sunlight and Sanskruti keeps it near a window with a constant breeze. In whose saucer will dry salt be obtained first? Give a reason.
Q.7 Give scientific reasons.
2 Marks
(1) A machine-operated churner is used in a large dairy.
(2) Raw salt obtained from salt pans requires further purification.
CHAPTER 3
Practice Set 2 – Solutions
Let’s Separate the Components
Q.1 (A) Choose the correct option.
(1) Removing chillies from vegetables
Answer: (b) Handpicking
(2) Substance that helps soil settle faster
Answer: (c) Alum
(3) Place where seawater is collected
Answer: (a) Salt pans
(4) Magnetic substances
Answer: (a) Iron, cobalt and nickel
Q.1 (B) Name the method of separation.
(1) Pouring out the clear liquid
Answer: Decantation
(2) Separating coarse particles from flour
Answer: Sieving
(3) Separating cream from milk
Answer: Churning using a machine-operated churner
(4) Removing trash by observing shape and colour
Answer: Handpicking
Q.2 Find the odd one out and state the reason.
(1) Iron, cobalt, nickel, chaff
Answer: Chaff
Iron, cobalt and nickel are magnetic substances. Chaff is non-magnetic.
(2) Strainer, fine sieve, filter paper, magnet
Answer: Magnet
A strainer, fine sieve and filter paper are used for filtration. A magnet is used for magnetic separation.
(3) Maharashtra, Gujarat, Tamil Nadu, Assam
Answer: Assam
The chapter mentions salt pans in Maharashtra, Gujarat, Tamil Nadu and Rajasthan. Assam is not included in this list.
Q.3 Complete the following processes.
Muddy water is kept undisturbed
→
Heavy soil particles settle
→
Soil collects at the bottom
Curd is churned
→
Butter particles stick together
→
A lump of butter is formed
Seawater is kept in sunlight
→
Water evaporates
→
Salt remains behind
Q.4 Distinguish between the following.
| Methods | First Method | Second Method |
|---|---|---|
| Sedimentation and Decantation | Sedimentation: Insoluble, heavy solid particles settle at the bottom of a liquid. | Decantation: The liquid above the settled particles is slowly poured into another vessel by tilting the vessel. |
| Handpicking and Winnowing | Handpicking: Components are separated by observing differences in their shape and colour and picking them out by hand. | Winnowing: Heavy and light substances are separated using their difference in weight and the help of wind. |
Q.5 Answer the following.
(1) Explain how grains and chaff are separated by dropping their mixture from a height.
Answer: When the mixture is dropped from a height, the heavy grains fall straight down. Chaff and other light trash are carried away by the wind. This method is called winnowing.
(2) Describe sedimentation and decantation using muddy water.
Answer: Muddy water is left undisturbed for a long time. The heavy, insoluble soil particles settle at the bottom. This is sedimentation. The vessel is then tilted, and the clear water above the soil is slowly poured into another vessel. This is decantation.
(3) How is salt obtained from seawater in salt pans?
Answer: Seawater is collected in salt pans along the coast. Sunlight changes the water into vapour. The water evaporates, and raw salt remains behind. Other separation methods are then used to remove stones, dirt and other impurities from the raw salt.
Q.6 Answer the activity-based questions.
(1) Separating oil and water
Answer: Two separate layers will form because oil and water do not mix. Water forms the lower layer, while oil forms the upper layer. Pour the mixture into a container having a small hole at the bottom. Open the hole and allow the lower water layer to flow into another vessel. Close the hole immediately when the water has flowed out and the oil reaches the hole. Oil will remain in the upper container.
(2) Salt solution kept in different places
Answer: Dry salt is expected to be collected first in Sanskruti’s saucer kept near the window with a constant breeze. Moving air carries away water vapour continuously and helps the water evaporate faster.
Q.7 Give scientific reasons.
(1) A machine-operated churner is used in a large dairy.
Answer: Large dairies handle a large quantity of milk. Machine-operated churners rotate liquids at high speed and separate cream in less time.
(2) Raw salt obtained from salt pans requires further purification.
Answer: Raw salt contains stones, dirt and other impurities. Therefore, various other separation methods must be used to obtain pure salt.