1.Which material would be best for making containers to store things at home or shops?
a) Opaque materials
b) Non-lustrous materials
c) Transparent materials
d) Soft materials
2. The process of arranging objects into groups on the basis of similar properties is called:
a) Mixing
b) Classification
c) Polishing
d) Isolation
3. Opaque materials:
a) Allow all light to pass
b) Allow some light to pass
c) Do not allow any light to pass
d) Are always transparent
4. What is the purpose of grouping materials?
a) To increase their weight
b) To confuse students
c) To study and use them easily
d) To break them
5. Which property describes a material that allows light to pass through it clearly?
a) Opaque
b) Translucent
c) Transparent
d) Lustrous
6. Which of these materials is non-lustrous?
a) Copper
b) Gold
c) Wood
d) Aluminium
7. Which of the following is a synthetic material?
a) Wood
b) Silk
c) Wool
d) Nylon
8. What is the property of metals that allows them to be drawn into wires?
a) Malleability
b) Ductility
c) Hardness
d) Flexibility
9. Which material is soluble in water?
a) Sand
b) Oil
c) Salt
d) Chalk
10. Metals lose their lustre over time because:
a) They melt
b) They react with air and moisture
c) They dry up
d) They become heavier
11. Which of the following materials is opaque?
a) Glass
b) Water
c) Wood
d) Air
12. Materials that allow light to pass through them are called:
a) Opaque
b) Transparent
c) Translucent
d) Reflective
13. Which of the following is NOT a metal?
a) Iron
b) Copper
c) Silver
d) Rubber
14. What material is commonly used to make mirrors?
a) Glass coated with silver
b) Plastic
c) Wood
d) Iron sheet
15. Which of the following is a soft material?
a) Iron
b) Cotton
c) Steel
d) Copper
16. Which of the following materials is transparent?
a) Glass
b) Cardboard
c) Wood
d) Stone
17. The SI unit of mass is:
a) Gram
b) Kilogram
c) Litre
d) Metre
18. The ability to be beaten into thin sheets is called:
a) Ductility
b) Malleability
c) Hardness
d) Brittleness
19. Which of the following materials is used to make clothes?
a) Glass
b) Wood
c) Cotton
d) Plastic
20. What property helps classify substances as soluble or insoluble?
a) Hardness
b) Solubility
c) Transparency
d) Flexibility
21.Sand in water will:
a) Dissolve completely
b) Float on the surface
c) Settle at the bottom
d) Make water transparent
22. You are provided with the following materials
(i) Magnifying glass (ii) Mirror
(iii) Stainless steel plate (iv) Glass tumbler
Which of the above materials will you identify as transparent?
(a) (i) and (ii)
(b) (i) and (iii)
(c) (i) and (iv)
(d) (iii) and (iv)
23. Which is an example of a translucent material?
a) Glass window
b) Wood
c) Butter paper
d) Steel plate
24. Which of the following is a good conductor of heat?
a) Plastic
b) Wood
c) Rubber
d) Copper
25. Which type of material does not allow light to pass but glows faintly?
a) Transparent
b) Translucent
c) Opaque
d) Reflective
26. What is matter?
a) Anything that can be seen
b) Anything that occupies space and has mass
c) Anything that is transparent
d) Anything that is shiny
27. Which material is commonly used for making kitchen utensils?
a) Cotton
b) Wood
c) Aluminum
d) Paper
28. Which of the following is insoluble in water?
a) Salt
b) Sugar
c) Sand
d) Lemon juice
29. Which is a property of liquids?
a) Fixed shape
b) Fixed volume
c) Rigid structure
d) None of the above
30. Paper is made from:
a) Metal
b) Plastic
c) Sand
d) Wood pulp
31. Which material is commonly used to make windows?
a) Wool
b) Cotton
c) Rubber
d) Glass
32. Which material is flexible?
a) Iron rod
b) Wooden stick
c) Rubber band
d) Stone
33. Chalk is:
a) Transparent
b) Hard
c) Soft and brittle
d) Liquid
34. Translucent materials:
a) Block all light
b) Allow full light to pass
c) Allow some light to pass partially
d) Reflect light
35. Pick one material from the following which is completely soluble
in water.
(a) Chalk powder
(b) Tea leaves
(c) Glucose
(d) Saw dust
1 Answer c) Transparent materials
2. Answer: b) Classification
3. Answer: c) Do not allow any light to pass
4. Answer: c) To study and use them easily
5. Answer: c) Transparent
6. Answer: c) Wood
7.Answer: d) Nylon
8. Answer: b) Ductility
9. Answer: c) Salt
10. Answer: b) They react with air and moisture
11.Answer: c) Wood
12. Answer: b) Transparent
13.Answer: d) Rubber
14. Answer: a) Glass coated with silver
15. Answer: b) Cotton
16.Answer: a) Glass
17.Answer: b) Kilogram
18. Answer: b) Malleability
19. Answer: c) Cotton
20. Answer: b) Solubility
21. Answer: c) Settle at the bottom
22. Answer: c)
23. Answer: c) Butter paper
24. Answer: d) Copper
25. Answer: b) Translucent
26. Answer: b) Anything that occupies space and has mass
27. Answer: c) Aluminum
28. answer c) sand
29. Answer: b) Fixed volume
30.Answer: d) Wood pulp
31. Answer: d) Glass
32. Answer: c) Rubber band
33. Answer: c) Soft and brittle
34. Answer: c) Allow some light to pass partially
35. Answer c) glucose
1. What is a material in scientific terms?
Answer: Any substance that is used to create an object is referred to as a material.
2. Can an object be made up of more than one material? Give an example.
Answer: Yes, an object can be made from more than one material; for example, a pen may be made up of plastic, metal, and ink.
3. What is classification? Why do we classify materials?
Answer: Classification is the method of arranging objects into groups based on common properties. We classify materials to study them easily and to observe patterns in properties.
4. Give three properties by which materials can be grouped.
Answer: Materials can be grouped based on their appearance (lustrous/non-lustrous), hardness/softness, and transparency (transparent/translucent/opaque).
5. What is meant by "lustrous" and "non-lustrous" materials? Give examples.
Answer: Lustrous materials have shiny surfaces, like metals (iron, copper, aluminium). Non-lustrous materials do not have shiny surfaces, such as wood, paper, rubber, or jute.
6. How can you distinguish between hard and soft materials? Explain with examples.
Answer: Hard materials cannot be compressed or scratched easily (e.g., stone, iron, brick), while soft materials can be compressed or scratched easily (e.g., cotton, eraser, pillow).
7. What is the difference between transparent, translucent and opaque materials? Give examples.
Answer:
- Transparent: things can be seen clearly through them (e.g., glass, water);
- Translucent: things can be seen but not clearly (e.g., butter paper, frosted glass);
- Opaque: things cannot be seen at all (e.g., wood, metals, cardboard).
8. Which property determines whether a material dissolves in water or not? Name two soluble and two insoluble substances.
Answer: Solubility in water determines this property. Sugar and salt are soluble in water, while sand and sawdust are insoluble.
10. Why can't a tumbler made of cloth be used for storing water?
Answer: Cloth is porous and soft, so it cannot hold water and will sag under the weight.
11. Why are different materials used for making balls for various sports?
Answer: Different sports require balls with specific properties like hardness, bounce level, and texture, so balls are made from materials best suited for those properties.
12. Is air a matter? Why or why not?
Answer: Yes, air is a matter because it has mass and occupies space.
13. State whether these statements are true or false (with correction):
- (i) Wood is translucent while glass is opaque.
- (ii) Aluminium foil has lustre while an eraser does not.
- (iii) Sugar dissolves in water whereas sawdust does not.
- (iv) An apple is a matter because it occupies no space and has mass.
Answer: False. Wood is opaque, while glass is transparent.
Answer: True.
Answer: True.
Answer: False. Apple is matter because it occupies space and has mass.
14. What are the SI units of mass and volume? How should they be written?
Answer: The SI unit of mass is kilogram ($$kg$$) and of volume is cubic metre ($$m^3$$), litre ($$L$$), or millilitre ($$mL$$). Always leave a space between the numerical value and the unit, e.g. $$500~\text{mL}$$, $$7~\text{kg}$$.
15. Why are containers used for storage usually transparent?
Answer: Transparent containers allow us to see the contents inside, making identification and usage easier.
16. Why do metals lose their lustre over time?
Answer: Metals lose their lustre because they react with air and moisture, forming a dull layer on their surfaces.
17. Can you give some examples of artificially made lustrous surfaces which are not metals?
Answer: Yes, some materials are made shiny by coating with plastic, wax, or other substances; for example, shiny plastic decorations or polished wooden surfaces.
18. Give examples of materials that are transparent, translucent, and opaque.
Answer:
- Transparent: Glass, water, air
- Translucent: Frosted glass, butter paper
- Opaque: Wood, metals, cardboard.
19. Explain with examples how materials can be classified by solubility.
Answer: If a substance dissolves in water, it is soluble (e.g., salt, sugar). If not, it is insoluble (e.g., sand, sawdust).