Matter Around Us Book Back Questions 6th Science Lesson 3

6th Science Lesson 3

3] Matter Around Us

Book Back Questions with Answer and Do You Know Box Content

Do You Know?

Solid 🡪 Liquid 🡪 Gas

‘Liquefaction of gases’ is the process by which substances in their gaseous state are converted to the liquid state. When the pressure on a gas is increased, its molecules come closer together, and the temperature is reduced. This removes enough energy to make it change from the gaseous state to the liquid state.

A mixture is an impure substance and contains more than one kind of particles. In the mixture the components are mixed in any proportion.

In washing machines water is squeezed out from clothes and they are dried. This method is called centrifugation.

Rice husk also called chaff is the hard coating or protective covering on a seed or grains. It protects the seed during the growing season. Husk can be used as building material, fertilizer, insulation material and fuel.

Combination of methods are used sometimes for complete separation. If the mixture of sand and salt in water has to be separated several methods like sedimentation, decantation, filtration, evaporation and condensation are used.

In most houses people use commercial water filter to remove not only the impurities but also to kill the harmful germs in water using UV rays. Reverse Osmosis (RO) is a process of removing impurities from water to make it potable.

Choose the correct answer:

1. _________________ is not made of matter.

(a) Gold ring

(b) Iron nail

(c) Light ray

(d) Oil drop

2. 200 ml of water is poured into a bowl of 400 ml capacity. The volume of water will be _______________

(a) 400 ml

(b) 600 ml

(c) 200 ml

(d) 800 ml

3. Seeds from water-melon can be removed by _________________

(a) hand-picking

(b) filtration

(c) magnetic separation

(d) decantation

4. Lighter impurities like dust when mixed with rice or pulses can be removed by _________________

(a) Filtration

(b) sedimentation

(c) decantation

(d) winnowing

5. ________________ is essential to perform winnowing activity.

(a) Rain

(b) Soil

(c) Water

(d) Air

6. Filtration method is effective in separating _______________ mixture.

(a) solid-solid

(b) solid-liquid

(c) liquid-liquid

(d) liquid-gas

7. Among the following __________________ is not a mixture.

(a) Coffee with milk

(b) lemon juice

(c) Water

(d) ice cream embedded with nuts

Fill in the blanks:

1. Matter is made up of _________________

2. In solids, the space between the particles is less than in _______________

3. Grains can be separated from their stalks by ________________

4. Chillies are removed from ‘Upma’ by _________________ method.

5. The method employed to separate clay particles from water is ________

6. Water obtained from tube wells is usually _____________ water.

7. Which among the following _____________ will get attracted to by magnet? (safety pins, pencil and rubber band)

State true or false. If false, correct the statement:

1. Air is not compressible.

2. Liquids have no fixed volume but have fixed shape.

3. Particles in solids are free to move.

4. When pulses are washed with water before cooking, water is separated from them by filtration.

5. Strainer is a kind of sieve which is used to separate a liquid from solid.

6. Grain and husk can be separated by winnowing.

7. Air is a pure substance.

8. Butter from curd is separated by sedimentation.

Complete the given analogy.

1. Solid: Rigidity: Gas : ______________

2. Large Inter-particle space: Gas :: _________: Solid.

3. Solid: Definite shape :: ____________ : shape of the vessel.

4. Husk-grains: winnowing :: sawdust –chalk piece: ________

5. Murukku from hot oil : ____________: coffee powder residue from decoction : _____________

6. Iron-sulphur mixture: ___________ :: Mustard seeds from Urad-dhal : rolling

Match the following:

Property	Example
Breaks easily (brittle)	Metal pan
Bends readily	Rubber band
Can be stretched easily	Cotton wool
Gets compressed easily	Mud pot
Gets heated readily	Plastic wire

A	B	C
1) Separation of visible undesirable components	a) Water mixed with chalk powder	i) Magnetic separation
2) Separation of heavier and lighter components	b) Sand and water	ii) Decantation
3) Separation of insoluble impurities	c) Iron impurities	iii) Filtration
4) Separation of magnetic components from non-magnetic components	d) Rice and stone	iv) Hand-picking
5) Separation of solids from liquids	e) Husk and paddy	v) Winnowing

Answers:

Choose the appropriate answers:

1. Light ray 2. 200 ml 3. Hand picking 4. Winnowing 5. Air 6. Solid-liquid 7. Water

Fill in the blanks:

1. Atoms 2. Liquid and Gases 3. Threshing 4. Hand picking 5. Filtration 6. Impure 7. Safety pins

State True or False:

1. False

Correct statement: Air is highly compressible.

2. False

Correct Statement: Liquid has fixed volume but have no fixed shape.

3. False

Correct Statement: Particles of solid cannot move freely.

4. False

Correct Statement: When pulses are washed with water before cooking water is separated from by the process of decantation.

5. True

6. True

7. False

Correct Statement: Air is a mixture of gas.

8. False

Correct Statement: Butter from curd is separated by churning.

Complete the given Analogy:

1. Flexibility 2. Little inter-particle space 3. Liquid 4. Filtration

5. Filtration and Filtration 6. Magnetic separation

Match the Following:

1.Mud pot 2. Plastic wire 3. Rubber band 4. Cotton wool 5. Metal pan

1. Separation of visible undesirable components – Rice and stone – Hand-picking

2. Separation of heavier and lighter components- Husk and Paddy- Winnowing

3. Separation of insoluble impurities – Water mixed with chalk powder- Filtration

4. Separation of magnetic components from non-magnetic components – Iron impurities- Magnetic separation

5. Separation of solids from liquids – Sand and water – Decantation