MCQs
1. A homogeneous mixture is also called:
A. Suspension
B. Colloid
C. Solution
D. Alloy
Answer: C
2. Which of the following is a heterogeneous mixture?
A. Sugar solution
B. Vinegar
C. Salt solution
D. Sand and water
Answer: D
3. In a solution, the substance that dissolves is called:
A. Solvent
B. Solute
C. Medium
D. Colloid
Answer: B
4. The substance that dissolves the solute is called:
A. Solvent
B. Suspension
C. Residue
D. Filtrate
Answer: A
5. ORS solution requires:
A. Random amounts of salt and sugar
B. Exact proportion of components
C. Only sugar
D. Only salt
Answer: B
6. Concentration of a solution refers to:
A. Total mass of solvent
B. Amount of solute dissolved in a given amount of solution/solvent
C. Boiling point of solution
D. Colour intensity only
Answer: B
7. Which concentration expression is commonly used for packaged foods?
A. % v/v
B. % m/m
C. ppm only
D. Molarity only
Answer: B
8. The concentration of saline used in hospitals is approximately:
A. 5% m/v
B. 1.5% m/v
C. 0.9% m/v
D. 10% m/v
Answer: C
9. Which expression is suitable for two miscible liquids?
A. % m/m
B. % m/v
C. % v/v
D. ppm
Answer: C
10. A solution that cannot dissolve more solute at a given temperature is called:
A. Unsaturated solution
B. Saturated solution
C. Dilute solution
D. Colloid
Answer: B
11. Solubility of most solid solutes in liquids generally:
A. Decreases with temperature
B. Remains constant
C. Increases with temperature
D. Becomes zero
Answer: C
12. The process of obtaining pure solid crystals from a saturated solution is:
A. Filtration
B. Distillation
C. Crystallization
D. Sublimation
Answer: C
13. Crystallization helps in:
A. Melting solids
B. Purification of solids
C. Producing gases
D. Condensation only
Answer: B
14. During crystallization, larger and well-shaped crystals form when cooling is:
A. Very rapid
B. Slow
C. Under pressure
D. Uneven
Answer: B
15. Separation of two miscible liquids with large boiling-point difference is done by:
A. Filtration
B. Sublimation
C. Distillation
D. Centrifugation
Answer: C
16. Acetone and water can be separated because they have:
A. Same density
B. Different boiling points
C. Same colour
D. Different solubilities only
Answer: B
17. In distillation, vapours are converted back into liquid by:
A. Sublimation
B. Condensation
C. Evaporation
D. Filtration
Answer: B
18. Fractional distillation is used when boiling-point difference is:
A. Very large
B. More than 100°C
C. Small
D. Zero
Answer: C
19. Paper chromatography separates substances based on:
A. Density only
B. Colour only
C. Difference in movement with solvent
D. Boiling point
Answer: C
20. In paper chromatography, the solvent level should be:
A. Above the ink spot
B. At the ink spot
C. Below the ink spot
D. Equal to paper height
Answer: C
21. Oil and water are:
A. Miscible liquids
B. Homogeneous mixture
C. Immiscible liquids
D. Colloids
Answer: C
22. Which apparatus is used to separate immiscible liquids?
A. Distillation flask
B. Separating funnel
C. Test tube
D. Evaporating dish
Answer: B
23. Camphor can be separated from sand by:
A. Filtration
B. Distillation
C. Sublimation
D. Crystallization
Answer: C
24. Sublimation is the process in which a solid changes directly into:
A. Liquid
B. Vapour
C. Plasma
D. Crystal
Answer: B
25. Which of the following is a sublimable substance?
A. Sand
B. Chalk powder
C. Camphor
D. Salt
Answer: C
26. A heterogeneous mixture in which particles remain suspended is called:
A. Solution
B. Alloy
C. Suspension
D. Emulsion
Answer: C
27. Which method separates heavier particles by rapid spinning?
A. Filtration
B. Sublimation
C. Centrifugation
D. Distillation
Answer: C
28. Alum is used in muddy water mainly for:
A. Evaporation
B. Coagulation
C. Distillation
D. Sublimation
Answer: B
29. Blood is an example of:
A. True solution
B. Suspension only
C. Colloid
D. Pure substance
Answer: C
30. Scattering of light by particles is called:
A. Reflection
B. Refraction
C. Tyndall effect
D. Dispersion
Answer: C
Assertion–Reason MCQs
31.
Assertion (A): Solutions do not show the Tyndall effect.
Reason (R): Particles in solutions are extremely small.
A. Both A and R are true, and R explains A
B. Both A and R are true, but R does not explain A
C. A is true but R is false
D. A is false but R is true
Answer: A
32.
Assertion (A): Oil and water form separate layers.
Reason (R): Oil and water are immiscible liquids.
A. Both A and R are true, and R explains A
B. Both A and R are true, but R does not explain A
C. A is true but R is false
D. A is false but R is true
Answer: A
33.
Assertion (A): Slow cooling produces larger crystals.
Reason (R): Particles get more time to arrange properly.
A. Both A and R are true, and R explains A
B. Both A and R are true, but R does not explain A
C. A is true but R is false
D. A is false but R is true
Answer: A
34.
Assertion (A): Suspensions can be separated by filtration.
Reason (R): Suspension particles are large in size.
A. Both A and R are true, and R explains A
B. Both A and R are true, but R does not explain A
C. A is true but R is false
D. A is false but R is true
Answer: A
Case-Based MCQs
Case Study 1
A student mixed black ink with water and performed paper chromatography.
35. The different colours obtained indicate that:
A. Ink is a pure substance
B. Ink contains multiple coloured components
C. Water changes colour chemically
D. Ink evaporates
Answer: B
36. In chromatography, the solvent moves upward due to:
A. Magnetic force
B. Gravity only
C. Capillary action
D. Friction
Answer: C
37. Why should the ink spot remain above solvent level initially?
A. To avoid dissolving directly into solvent
B. To increase evaporation
C. To stop colour separation
D. To increase boiling point
Answer: A
Case Study 2
A muddy water sample was treated with alum and left undisturbed.
38. Alum helps by:
A. Increasing solubility
B. Causing coagulation
C. Producing crystals
D. Lowering boiling point
Answer: B
39. After coagulation, impurities can be removed by:
A. Filtration or decantation
B. Distillation only
C. Sublimation only
D. Melting
Answer: A
Competency-Based MCQs
40. Which method would be best for obtaining pure copper sulfate crystals from solution?
A. Distillation
B. Filtration
C. Crystallization
D. Sedimentation
Answer: C
41. A mixture contains naphthalene and sand. Which property helps separate them?
A. Density
B. Sublimation tendency
C. Colour
D. Solubility in water
Answer: B
42. Which method is MOST suitable for separating plasma from blood?
A. Sublimation
B. Chromatography
C. Centrifugation
D. Distillation
Answer: C
43. Which mixture will definitely show the Tyndall effect?
A. Salt solution
B. Sugar solution
C. Milk
D. Vinegar
Answer: C
44. Why are colloids different from suspensions?
A. Colloid particles settle quickly
B. Colloids are always transparent
C. Colloid particles do not settle easily
D. Colloids are pure substances
Answer: C
45. Which process is used in petroleum refineries?
A. Sublimation
B. Fractional distillation
C. Coagulation
D. Chromatography
Answer: B
46. A student wants to recover both salt and water from salt solution. Which method is suitable?
A. Evaporation
B. Filtration
C. Distillation
D. Sublimation
Answer: C
47. Which mixture is correctly classified as a colloid?
A. Salt solution
B. Sand in water
C. Milk
D. Brass
Answer: C
48. The Tyndall effect occurs because particles:
A. Absorb light completely
B. Scatter light
C. Produce light
D. Reflect sound
Answer: B
49. Which process changes vapour directly into solid?
A. Evaporation
B. Condensation
C. Deposition
D. Fusion
Answer: C
50. Which statement BEST describes suspensions?
A. Homogeneous mixtures with invisible particles
B. Pure substances only
C. Heterogeneous mixtures with visible particles that may settle
D. Mixtures of gases only
Answer: C
