Maximum Marks: 50 Matter in Our Surroundings Time: 1 Hour
Section A – Very Short Answer Questions (1 mark each)
(Answer in one sentence. Attempt all.). [1 × 5 = 5 marks]
1. Define matter.
2. What is the SI unit of temperature?
3. Name the state of matter that has neither definite shape nor definite
volume.
4. What is the boiling point of water in Celsius?
5. Give one example of sublimation.
Section B – Short Answer Questions (2 marks each)
(Answer in 30–40 words.). [2 × 5 = 10 marks]
6. List any two characteristics of particles of matter.
7. Differentiate between evaporation and boiling (any two points).
8. Why do we feel cool when we apply alcohol on our skin?
9. Define latent heat of fusion.
10. Why does a desert cooler cool better on a hot dry day?
Section C – Short Answer Questions (3 marks each)
(Answer in about 50–60 words.). [3 × 5 = 15 marks]
11. Describe how matter can change from one state to another.
12. State and explain three factors affecting the rate of
evaporation.
13. How does pressure affect the state of matter? Give an
example.
14. Draw a labeled diagram showing the change of state of matter
(solid, liquid, gas) with heat addition/removal.
15. Differentiate between the three states of matter on the basis
of:
a) Shape
b) Volume
c) Compressibilityl
1. Multiple Choice Questions (1 mark each)
[5 × 1 = 5 marks]
1. Which of the following has the highest kinetic energy?
a) Ice. b) Water. c) Steam. d) Salt
2. Which phenomenon occurs during the conversion of a gas to a liquid?
a) Sublimation. b) Condensation
c) Melting. d) Freezing
3. The rate of evaporation increases with:
a) Decrease in surface area
b) Increase in humidity
c) Decrease in temperature
d) Increase in wind speed
4. Which of the following is a sublimable substance?
a) Salt. b) Camphor
c) Sugar. d) Sand
5. Which state of matter is highly compressible?
a) Solid. b) Liquid
c) Gas. d) Plasma
2. Fill in the Blanks (1 mark each). [5 × 1 = 5 marks]
6. The temperature at which a liquid starts boiling is called its
__________.
7. Matter is made up of __________ particles.
8. The change of solid directly into gas is called __________.
9. __________ is the amount of heat energy required to change 1 kg of
solid into liquid at its melting point.
10. The gaseous state of water is called __________.
3. Match the Following (1 mark each). [5 × 1 = 5 marks]
Column A Column B
11. Latent heat a) Movement of particles
12. Evaporation b) Heat without temperature rise
Column A Column B
13. Interconversion of states c) Drying of wet clothes
14. Diffusion d) Boiling and condensation
15. Compressibility e) Property of gases
4. Assertion and Reasoning (1 mark each)
[5 × 1 = 5 marks]
For questions 16–20, choose:
A. Both Assertion and Reason are true and Reason is the correct
explanation.
B. Both Assertion and Reason are true but Reason is not the correct
explanation.
C. Assertion is true but Reason is false.
D. Both Assertion and Reason are false.
16. Assertion: Gases are more compressible than solids.
Reason: Gases have large intermolecular spaces.
17. Assertion: Steam causes more severe burns than boiling
water.
Reason: Steam contains more latent heat than boiling water.
18. Assertion: Solids can flow easily.
Reason: Solids have fixed shape and volume.
19. Assertion: Evaporation takes place only at the boiling point.
Reason: Particles of a liquid gain enough energy at boiling point
to change into gas.
20. Assertion: On increasing the surface area, the rate of
evaporation increases.
Reason: More particles are exposed to air for evaporation.
