✅ 20 Multiple Choice Questions (MCQs)
1. Which of the following is a pure substance?
a) Air
b) Milk
c) Iron
d) Soil
➤ Ans: c) Iron
2. A homogeneous mixture is:
a) Soil
b) Sugar in water
c) Oil and water
d) Sand and iron filings
➤ Ans: b) Sugar in water
3. Which technique is used to separate dyes in ink?
a) Filtration
b) Evaporation
c) Chromatography
d) Distillation
➤ Ans: c) Chromatography
4. Which of the following is not a method of separation of components of a mixture?
a) Sublimation
b) Crystallization
c) Condensation
d) Filtration
➤ Ans: c) Condensation
5. Which process is used to obtain pure salt from sea water?
a) Filtration
b) Decantation
c) Evaporation
d) Sedimentation
➤ Ans: c) Evaporation
6. A solution that has more solute than it can hold at a given temperature is:
a) Unsaturated
b) Saturated
c) Supersaturated
d) Diluted
➤ Ans: c) Supersaturated
7. What is the Tyndall effect?
a) Scattering of light by true solutions
b) Scattering of light by particles in a colloid
c) Refraction of light
d) Absorption of light
➤ Ans: b) Scattering of light by particles in a colloid
8. Which of these is a colloid?
a) Salt solution
b) Blood
c) Vinegar
d) Air
➤ Ans: b) Blood
9. Which of these is a suspension?
a) Sugar solution
b) Paint
c) Copper sulphate solution
d) Alcohol and water
➤ Ans: b) Paint
10. Which property is not shown by a colloid?
a) Heterogeneous
b) Cannot be seen with naked eyes
c) Settles down
d) Shows Tyndall effect
➤ Ans: c) Settles down
11. A solution that cannot dissolve any more solute at a given temperature is called:
a) Dilute
b) Concentrated
c) Saturated
d) Supersaturated
➤ Ans: c) Saturated
12. Which technique is used to separate a mixture of salt and ammonium chloride?
a) Filtration
b) Sublimation
c) Distillation
d) Chromatography
➤ Ans: b) Sublimation
13. Which of the following is not a colloid?
a) Fog
b) Smoke
c) Milk
d) Salt solution
➤ Ans: d) Salt solution
14. Milk is an example of:
a) True solution
b) Suspension
c) Colloid
d) None of these
➤ Ans: c) Colloid
15. Components of petroleum are separated by:
a) Simple distillation
b) Fractional distillation
c) Filtration
d) Crystallization
➤ Ans: b) Fractional distillation
16. Which is a heterogeneous mixture?
a) Vinegar
b) Sugar solution
c) Oil and water
d) Alcohol in water
➤ Ans: c) Oil and water
17. The solute in brass is:
a) Zinc
b) Copper
c) Tin
d) Lead
➤ Ans: a) Zinc
18. Which of these is a physical change?
a) Burning
b) Melting
c) Rusting
d) Fermentation
➤ Ans: b) Melting
19. In a solution, the component present in larger quantity is called:
a) Solute
b) Solvent
c) Residue
d) Filtrate
➤ Ans: b) Solvent
20. Which of these is used to test Tyndall effect?
a) Torch
b) Magnifying glass
c) Microscope
d) Heater
➤ Ans: a) Torch
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✍️ 20 Short Answer Questions
1. Define a pure substance.
2. What is the difference between a compound and a mixture?
3. Define solution.
4. What is the Tyndall effect?
5. What is a saturated solution?
6. Define solute and solvent with an example.
7. What is meant by concentration of a solution?
8. How can we separate a mixture of sand and water?
9. What is chromatography?
10. Define a colloid and give one example.
11. Mention one difference between suspension and colloid.
12. State the principle of sublimation.
13. Write two examples of homogeneous mixtures.
14. Write two examples of heterogeneous mixtures.
15. What is fractional distillation?
16. Why does milk show the Tyndall effect?
17. How can you separate salt from sea water?
18. What is meant by crystallization?
19. Classify the following as pure substance or mixture: water, soil, gold, air.
20. Define centrifugation and give one use.
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🧠 20 Long Answer Questions
1. Explain the different types of mixtures with examples.
2. Describe the properties of a solution.
3. Differentiate between true solution, suspension, and colloid.
4. What is Tyndall effect? How will you demonstrate it in a lab?
5. Write methods to separate components of a mixture with examples.
6. Describe the process of distillation and give one application.
7. How is crystallization better than evaporation for separating solids?
8. Explain chromatography with a diagram.
9. What is the principle of fractional distillation? How is it used in separating petroleum components?
10. Write differences between homogeneous and heterogeneous mixtures.
11. How will you prepare a saturated and unsaturated solution in the lab?
12. Describe how to separate a mixture of salt, sand, and ammonium chloride.
13. What are colloids? State their properties with examples.
14. Define solubility. What factors affect the solubility of a substance?
15. Differentiate between elements, compounds, and mixtures with examples.
16. What are the types of pure substances? Explain with examples.
17. Why are alloys considered mixtures? Give examples and reasons.
18. Describe the separation of cream from milk using centrifugation.
19. How will you prove that milk is a colloid?
20. Explain how matter can be classified based on composition.
