Worksheet – Science (Class IX)

📘 Worksheet – Science (Class IX)

Chapters: Matter in Our Surroundings, Is Matter Around Us Pure, Atoms and Molecules

Type: Multiple Choice Questions 

Matter in Our Surroundings

1. Which of the following has the highest kinetic energy?

a) Solid

b) Liquid

c) Gas

d) Plasma

2. Conversion of liquid into vapour at any temperature is called:

a) Boiling

b) Condensation

c) Evaporation

d) Sublimation

3. Which factor does not affect the rate of evaporation?

a) Temperature

b) Surface area

c) Air pressure

d) Humidity

4. The property of matter responsible for diffusion is:

a) Inertia

b) Compressibility

c) Intermolecular space

d) Intermolecular force

5. Which of the following shows sublimation?

a) Ice → Water

b) Camphor → Vapour

c) Steam → Water

d) Water → Steam

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Is Matter Around Us Pure

6. A mixture of salt and water can be separated by:

a) Filtration

b) Evaporation

c) Chromatography

d) Sublimation

7. Which of the following is a heterogeneous mixture?

a) Air

b) Soda water

c) Soil

d) Alloy

8. The technique used to separate dyes in ink is:

a) Filtration

b) Chromatography

c) Distillation

d) Sublimation

9. Brass is a mixture of:

a) Copper and Zinc

b) Copper and Tin

c) Copper and Aluminium

d) Zinc and Iron

10. The boiling point of pure water at normal pressure is:

a) 100 °C

b) 0 °C

c) 273 K

d) 373 °C

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Atoms and Molecules

11. Who gave the Law of Conservation of Mass?

a) Dalton

b) Lavoisier

c) Proust

d) Rutherford

12. The formula of calcium hydroxide is:

a) CaOH

b) Ca(OH)₂

c) CaO₂H

d) Ca₂OH

13. Which of the following has molecular mass = 18 u?

a) O₂

b) H₂O

c) NH₃

d) CH₄

14. The number of atoms in 1 molecule of H₂SO₄ is:

a) 6

b) 7

c) 5

d) 4

15. 1 mole of any substance contains:

a) 6.022 × 10²³ particles

b) 6.022 × 10²² particles

c) 3.011 × 10²³ particles

d) 12.044 × 10²³ particles

16. The SI unit of mass is:

a) Gram

b) Kilogram

c) Mole

d) Dalton

17. Which of the following is a molecule of element?

a) H₂O

b) CO₂

c) H₂

d) NaCl

18. Relative atomic mass of nitrogen is:

a) 7

b) 14

c) 28

d) 21

19. The chemical formula of magnesium chloride is:

a) MgCl

b) Mg₂Cl

c) MgCl₂

d) Mg₂Cl₂

20. Molecular mass of CO₂ is:

a) 28 u

b) 32 u

c) 44 u

d) 46 u

✅ Total: 20 Marks (1 mark each)

Matter in Our Surroundings

1. c) Gas

2. c) Evaporation

3. c) Air pressure

4. c) Intermolecular space

5. b) Camphor → Vapour

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Is Matter Around Us Pure

6. b) Evaporation

7. c) Soil

8. b) Chromatography

9. a) Copper and Zinc

10. a) 100 °C

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Atoms and Molecules

11. b) Lavoisier

12. b) Ca(OH)₂

13. b) H₂O

14. b) 7

15. a) 6.022 × 10²³ particles

16. b) Kilogram

17. c) H₂

18. b) 14

19. c) MgCl₂

20. c) 44 u

✅ Answer Key Complete (20/20)