NCERT Class 6 Science Chapter 6 Materials Around Us Important Extra Questions and Answers

Very Short Answer Type Questions

Question 1.
Give one example of translucent material.
Answer:
A tissue paper

Question 2.
What property distinguishes hard materials from soft materials?
Answer:
Hard materials cannot be easily compressed or scratched, while soft materials can be compressed or scratched easily.

Question 3.
Which gas is readily dissolved in water?
Answer:
Oxygen gets dissolved in water very easily and is useful for the survival of aquatic plants and animals.
Reference diagram for Q. 4 and Q. 5.

• Aqeel poured liquid 1 and liquid 2, each to a jar of water.
• He stirred he mixture in each jar with a spoon.
• He allowed the mixtures to rest for 10 mins.

Question 4.
Are liquid 1 and liquid 2 soluble in water?
Write Yes or No in the space given the table below.

Type of liquid added to water	Is it soluble in water?
Liquid 1
Liquid 2

Answer:

Type of liquid added to water	Is it soluble in water?
Liquid 1	Yes
Liquid 2	No

Question 5.
Which of the following must Aqeel keep the same in his activity? Circle ‘Yes’ or ‘No’ for the correct response.

Should this be kept the same in the activity?	Yes or No?
Amount of the two liquids added to water	Yes/No
Amount of water in both the jars	Yes/No
Amount of time the two mixtures were stirred	Yes/No

Answer:

Should this be kept the same in the activity?	Yes or No?
Amount of the two liquids added to water	Yes
Amount of water in both the jars	Yes
Amount of time the two mixtures were stirred	Yes

Short Answer Type Questions

Question 1.
Why are gold and silver shinier as compared to iron?
Answer:
Iron corrodes easily in the presence of air and moisture and it loses its shine and appears dull whereas, gold and silver maintain their shine and do not cor -rode easily.

Question 2.
Give two reasons for the need to group different materials.
Answer:
(a) We need to group materials for their easy classification.
(b) We, need to group materials to study their properties.

Question 3.
Why is wood most suitable material for making a table?
Answer:
Wood is very hard and durable which makes it suitable for making table. It is also because of ease of construction.

Long Answer Type Questions

Question 1.
Classify the following materials on the basis of solubility and transparency: salt, flower, oxygen, sand, piece of glass, sugar crystal, oiled butter paper and coconut oil.
Answer:

Material	Solubility	Transparency
Salt	Soluble	Opaque
Flower	Insoluble	Opaque
Oxygen	Soluble	Transparent
Sand	Insoluble	Opaque
Piece of glass	Insoluble	Transparent
Sugar crystal	Soluble	Transparent
Oiled butter paper	Insoluble	Translucent
Hot coconut oil	Insoluble	Transparent

Question 2.
Differentiate between:
(a) Opaque and transparent materials.
(b) Soluble and insoluble.
(c) Lustrous and non-lustrous.
(d) Malleable and brittle
Answer:
(a) Transparent materials allow most of the light falling on them to pass through, whereas opaque materials do not allow light to pass through.
(b) Soluble materials dissolve in a solvent, whereas insoluble materials do not dissolve and remain separate.
(c) Materials that shine are called lustrous and those which do not called non-lustrous.
(d) A solid material is said to be malleable if it can be beaten or pressed into sheets or foils. A solid material that breaks on being bent, beaten or pressed is called brittle.

Question 1.
List any five objects and write the names of materials they are made up of.
Answer:

Object	Material it is made up of
1. Table	Wood
2. Spoon	Steel
3. Spectacles	Glass, steel and plastic
4. Book	Paper
5. Toys	Plastic and rubber

Question 2.
Name any four objects which can be made from wood.
Answer:
Table, chair, stool and door.

Question 3.
Group the objects given below on the basis of hardness/ softness:
Earthen lamp, wooden scale, pencil, tennis ball, screw driver, wool, wax, eraser, sharpener, soap.
Answer:

Hard objects	Soft objects
Earthen lamp	Tennis ball
Wooden scale	Wool
Pencil	Wax
Screw drivfer	Soap
Sharpener	Eraser

Question 4.
Select those objects from the following which have lustre: Steel bowl, cotton shirt, glass bowl, brass lamp, bell, soap cake
Answer:
Steel bowl, brass lamp and bell have lustre.

Question 5.
List any four materials which can be used to make a spoon.
Answer:
Steel, brass, wood and plastic can be used to make a spoon.

 

Question 6.
Can a cricket ball be used to play tennis?
Answer:
Cricket ball cannot be used to play tennis because it is heavy and has low bounce.

Question 7.
Which of the following objects can be classified as soft?
Chalk, chair, brick, wax, wool, steel bowl and sponge
Answer:
Chalk, wax, wool and sponge are soft.

Question 8.
What are transparent materials? Give two examples of transparent objects.
Answer:
The materials through which the things can be seen clearly, are called transparent. For example, glass and water.

Question 9.
Name three materials which are soluble in water and three which are insoluble.
Answer:
Sugar, salt and washing soda are soluble in water. Sand, sawdust and wax are insoluble in water.

Question 10.
What are opaque materials? Give two examples of opaque objects.
Answer:
Materials, through which we are not able to see at all, are called opaque. For example, metal sheet and wooden board.

 

Question 11.
Which of the following liquids are soluble in water and which are insoluble? Honey, mustard oil, alcohol, kerosene, mnegar and petrol.
Answer:
Honey, alcohol and vinegar are soluble in water. Mustard oil, kerosene and petrol are insoluble in water.

Question 12.
State whether the statements given below are True (T) or – False (F)
(i) Chalk dissolves in water
(ii) Spoon is opaque, while glass is transparent
(iii) Sand settles down in water
(iv) Oil is insoluble in water
(v) Glucose is insoluble in water
Answer:
(i) Chalk dissolves in water (F)
(ii) Spoon is opaque, while glass is transparent (T)
(iii) Sand settles down in water (T)
(iv) Oil is insoluble in water (T)
(v) Glucose is insoluble in water (F)

Question 13.
Oxygen gas is soluble in water. It dissolves in water present in various water bodies. What is the importance of this oxygen gas dissolved in water?
Answer:
Oxygen gas, dissolved in water, is important for the survival of animals and plants that live in water.

Question 14.
Match the objects given below with ‘the materials from which they could be made.

Object	Materials
Chair	Leather
Book	Plastic
Toy	Paper
Tumbler	Wood
Shoes	Glass

Answer:

Object	Materials
Chair	Wood
Book	Paper
Toy 1	Plastic
Tumbler	Glass
Shoes	Leather

Question 15.
Give the units in which mass and volume are measured.
Answer:
Mass is measured in units of gram (g) and kilogram (kg) The units to measure volume are litre (L), millilitre (mL) and cubic metre (m3).

 

Question 16.
Why is water considered as matter?
Answer:
Water is considered as matter because it has mass and occupies space.

Question 17.
Name a material which is transparent and is not visible.
Answer:
Air

Question 18.
Which is heavier, 1 L of water or 1 L of sand?
Answer:
1 L of sand is heavier than 1 L of water.

Question 19.
Why does a piece of wood float on water?
Answer:
Wood floats on water because it is lighter than water.