Class 9 Science Chapter 5 MCQs – Exploring Mixtures and Their Separation

Class 9 Science Chapter 5 MCQs – Exploring Mixtures and Their Separation are designed to help students understand and revise the important concepts of mixtures and different methods used to separate their components.

These 50 MCQs with answers cover solutions, solutes, solvents, suspensions, colloids, concentration, filtration, evaporation, crystallisation, distillation, chromatography, centrifugation, magnetic separation, sublimation, and separating funnel.

1. What is a mixture?

A. A substance made of only one type of particle
B. A combination of two or more substances that are not chemically combined
C. A compound formed by a chemical reaction
D. A pure element

Answer: B. A combination of two or more substances that are not chemically combined

2. Which of the following is a mixture?

A. Oxygen
B. Gold
C. Air
D. Distilled water

Answer: C. Air

3. Which of the following is a homogeneous mixture?

A. Sand and water
B. Oil and water
C. Salt solution
D. Soil

Answer: C. Salt solution

4. A homogeneous mixture has:

A. Uniform composition throughout
B. Non-uniform composition throughout
C. Only solid components
D. Only liquid components

Answer: A. Uniform composition throughout

5. Which of the following is a heterogeneous mixture?

A. Sugar solution
B. Air
C. Salt solution
D. Sand and water

Answer: D. Sand and water

6. A solution is:

A. A pure substance
B. A homogeneous mixture
C. A heterogeneous mixture
D. A compound only

Answer: B. A homogeneous mixture

7. In a salt solution, salt is the:

A. Solvent
B. Solute
C. Suspension
D. Residue

Answer: B. Solute

8. In a sugar solution prepared using water, water is the:

A. Solute
B. Solvent
C. Residue
D. Colloid

Answer: B. Solvent

9. The substance that dissolves another substance in a solution is called:

A. Solute
B. Solvent
C. Residue
D. Filtrate

Answer: B. Solvent

10. The substance that gets dissolved in a solution is called:

A. Solvent
B. Solute
C. Filtrate
D. Sediment

Answer: B. Solute

11. Which of the following is an example of a gas dissolved in a liquid?

A. Salt water
B. Carbon dioxide in soda
C. Brass
D. Sand in water

Answer: B. Carbon dioxide in soda

12. Brass is a mixture of:

A. Copper and iron
B. Copper and zinc
C. Iron and carbon
D. Aluminium and copper

Answer: B. Copper and zinc

13. Which type of mixture is brass?

A. Solid-liquid mixture
B. Liquid-liquid mixture
C. Solid-solid mixture
D. Gas-liquid mixture

Answer: C. Solid-solid mixture

14. A solution containing the maximum amount of solute that can dissolve at a given temperature is called:

A. Dilute solution
B. Unsaturated solution
C. Saturated solution
D. Suspension

Answer: C. Saturated solution

15. A solution that can dissolve more solute at a given temperature is called:

A. Saturated solution
B. Unsaturated solution
C. Suspension
D. Colloid

Answer: B. Unsaturated solution

16. Which of the following is a characteristic of a true solution?

A. Its particles can be seen with the naked eye
B. Its particles settle down on standing
C. It is homogeneous
D. It can always be separated by filtration

Answer: C. It is homogeneous

17. Which method can be used to separate an insoluble solid from a liquid?

A. Filtration
B. Distillation
C. Chromatography
D. Sublimation

Answer: A. Filtration

18. In filtration, the liquid that passes through the filter paper is called:

A. Residue
B. Filtrate
C. Solute
D. Sediment

Answer: B. Filtrate

19. The solid left behind on the filter paper is called:

A. Filtrate
B. Residue
C. Solvent
D. Distillate

Answer: B. Residue

20. Which method is commonly used to separate sand from water?

A. Filtration
B. Sublimation
C. Distillation
D. Chromatography

Answer: A. Filtration

21. Which method can be used to obtain salt from salt water?

A. Filtration
B. Evaporation
C. Magnetic separation
D. Sedimentation only

Answer: B. Evaporation

22. Evaporation separates a dissolved solid from a solution by:

A. Freezing the solvent
B. Removing the solvent as vapour
C. Magnetising the solute
D. Filtering the solution

Answer: B. Removing the solvent as vapour

23. Which method is preferred when we want to obtain pure crystals of a dissolved solid?

A. Filtration
B. Crystallisation
C. Magnetic separation
D. Decantation

Answer: B. Crystallisation

24. Crystallisation is useful for:

A. Separating insoluble solids only
B. Purifying certain soluble solids
C. Separating gases only
D. Separating magnetic materials only

Answer: B. Purifying certain soluble solids

25. Which method is commonly used to separate two miscible liquids having different boiling points?

A. Filtration
B. Distillation
C. Magnetic separation
D. Sublimation

Answer: B. Distillation

26. Distillation involves:

A. Melting followed by freezing
B. Evaporation followed by condensation
C. Filtration followed by sedimentation
D. Sublimation followed by filtration

Answer: B. Evaporation followed by condensation

27. Which property is mainly used in distillation to separate liquids?

A. Difference in colour
B. Difference in boiling points
C. Difference in magnetic properties
D. Difference in particle size only

Answer: B. Difference in boiling points

28. Which method can be used to obtain pure water from salt solution?

A. Filtration
B. Distillation
C. Magnetic separation
D. Chromatography

Answer: B. Distillation

29. The liquid collected after condensation during distillation is called:

A. Residue
B. Distillate
C. Solute
D. Sediment

Answer: B. Distillate

30. Which method is commonly used to separate different coloured substances present in ink?

A. Filtration
B. Chromatography
C. Evaporation
D. Decantation

Answer: B. Chromatography

31. Chromatography is based mainly on differences in:

A. Attraction and movement of components between a stationary medium and a moving solvent
B. Magnetic properties only
C. Particle size only
D. Boiling points only

Answer: A. Attraction and movement of components between a stationary medium and a moving solvent

32. Which technique is useful for separating pigments present in a mixture?

A. Chromatography
B. Filtration
C. Sedimentation
D. Decantation

Answer: A. Chromatography

33. Which method can be used to separate iron filings from sand?

A. Evaporation
B. Magnetic separation
C. Distillation
D. Chromatography

Answer: B. Magnetic separation

34. Magnetic separation depends on:

A. Difference in boiling points
B. Magnetic properties of one component
C. Difference in solubility only
D. Difference in density only

Answer: B. Magnetic properties of one component

35. Which method is suitable for separating ammonium chloride from a mixture containing sand?

A. Filtration
B. Sublimation
C. Distillation
D. Decantation

Answer: B. Sublimation

36. Sublimation is the process in which a substance changes:

A. From solid directly to gas
B. From liquid to solid only
C. From gas to liquid only
D. From solid to liquid only

Answer: A. From solid directly to gas

37. Which of the following substances can undergo sublimation?

A. Sand
B. Common salt
C. Ammonium chloride
D. Sugar

Answer: C. Ammonium chloride

38. Which method can be used to separate two immiscible liquids such as oil and water?

A. Separating funnel
B. Chromatography
C. Sublimation
D. Evaporation

Answer: A. Separating funnel

39. Oil and water form:

A. A homogeneous mixture
B. A heterogeneous mixture of immiscible liquids
C. A pure substance
D. A solution

Answer: B. A heterogeneous mixture of immiscible liquids

40. The separation of oil and water using a separating funnel is based mainly on their difference in:

A. Density and immiscibility
B. Colour
C. Boiling point only
D. Magnetic properties

Answer: A. Density and immiscibility

41. Which method can be used to separate cream from milk?

A. Centrifugation
B. Sublimation
C. Chromatography
D. Magnetic separation

Answer: A. Centrifugation

42. Centrifugation separates components mainly on the basis of differences in:

A. Density
B. Colour
C. Boiling point
D. Magnetism

Answer: A. Density

43. Which of the following is a colloid?

A. Salt solution
B. Sugar solution
C. Milk
D. Distilled water

Answer: C. Milk

44. Which of the following is a suspension?

A. Salt solution
B. Sugar solution
C. Muddy water
D. Air

Answer: C. Muddy water

45. Which statement about a suspension is correct?

A. Its particles are too small to settle
B. Its particles settle down when left undisturbed
C. It is always transparent
D. It cannot be separated by filtration

Answer: B. Its particles settle down when left undisturbed

46. Which of the following can be separated by ordinary filtration?

A. Salt from salt solution
B. Sugar from sugar solution
C. Sand from water
D. Alcohol from water

Answer: C. Sand from water

47. A mixture of two or more substances that retain their individual properties can generally be separated by:

A. Physical methods
B. Nuclear reactions only
C. Chemical reactions only
D. No method

Answer: A. Physical methods

48. Which separation method would be most suitable for separating a mixture of salt and sand?

A. Magnetic separation
B. Dissolving salt in water, filtration, followed by evaporation
C. Sublimation only
D. Chromatography only

Answer: B. Dissolving salt in water, filtration, followed by evaporation

49. A student wants to separate a mixture of iron filings, sand and salt. Which sequence is most appropriate?

A. Add water → filter → use magnet → evaporate
B. Use magnet → add water → filter → evaporate
C. Evaporate → use magnet → filter
D. Use chromatography → filter → evaporate

Answer: B. Use magnet → add water → filter → evaporate

50. Which statement best explains why different separation methods are used for different mixtures?

A. Every mixture can be separated by filtration
B. Different components have different physical properties
C. All mixtures have identical components
D. Separation methods depend only on the colour of substances

Answer: B. Different components have different physical properties

Quick Revision: Important Separation Methods

Key Concepts to Remember

Students should be able to explain:

• What is a mixture?
• Difference between homogeneous and heterogeneous mixtures
• Solute and solvent
• Saturated and unsaturated solutions
• Solutions, suspensions and colloids
• Filtration and evaporation
• Crystallisation
• Distillation
• Chromatography
• Centrifugation
• Magnetic separation
• Sublimation
• Separating funnel
• Choosing the correct separation technique for a particular mixture

More Class 9 Science Chapter 5 Resources

For complete preparation of Chapter 5 – Exploring Mixtures and Their Separation, students should also practise:

• Class 9 Science Chapter 5 Notes
• Class 9 Science Chapter 5 Mind Map
• Class 9 Science Chapter 5 Important Questions
• Class 9 Science Chapter 5 Assertion & Reason Questions
• Class 9 Science Chapter 5 Case-Based Questions
• Class 9 Science Chapter 5 Question Bank
• Class 9 Science Chapter 5 Practice Questions
• Complete Class 9 Science Notes – All Chapters

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