Purification techniques: crystallization sublimation distillation differential extraction chromatography and their applications - Question Bank
1. Which purification technique is suitable for separating an organic compound from water-soluble impurities if the compound itself is insoluble in water?
2. Which property is NOT typically exploited for separation in chromatography?
3. In differential extraction, the solvent that extracts the solute more efficiently is known as the:
4. Crystallization is generally most effective for purifying:
5. Which technique is used to purify heat-sensitive compounds by reducing the boiling point under reduced pressure?
6. What is the 'tailing' phenomenon in chromatography?
7. Which of the following is a major advantage of chromatography over other purification techniques?
8. In partition chromatography, separation occurs based on the difference in the ______ of the solute between two immiscible liquid phases.
9. Which purification technique is based on the difference in vapor pressure of components in a liquid mixture?
10. A separatory funnel is used in which purification technique?
11. Which chromatography technique is often used for rapid qualitative analysis of reaction mixtures or purity checks?
12. What is the primary purpose of using a fractionating column in fractional distillation?
13. Which purification method is generally NOT suitable for purifying ionic compounds?
14. Filtration is a technique used to separate:
15. Which of the following is a characteristic of the mobile phase in chromatography?
16. In Gas Chromatography (GC), the separation of components is based on their differences in:
17. Steam distillation is a type of distillation where the mixture is heated by passing steam through it. This is effective for compounds that are:
18. Which of the following methods is used to separate an organic acid from a mixture of neutral compounds and organic bases?
19. When purifying a solid by crystallization, the ideal solvent should:
20. Which purification technique is most suitable for separating components of a mixture based on their different affinities for the stationary and mobile phases?
21. In Thin Layer Chromatography (TLC), the stationary phase is typically a thin layer of silica gel or alumina coated on a:
22. Which distillation technique is used to separate a volatile liquid from a non-volatile solid, or liquids with very large boiling point differences?
23. The process of dissolving a solid in a suitable solvent, filtering, and then allowing crystals to form upon cooling is called:
24. Which of the following is a limitation of sublimation as a purification technique?
25. Differential extraction is particularly useful for separating a solute from a mixture when the solute has a higher solubility in:
26. In chromatography, Rf value is defined as the ratio of the distance traveled by the:
27. Which purification technique is used to isolate compounds that are insoluble in a particular solvent?
28. Crystallization works best when the desired compound is ______ soluble at room temperature and ______ soluble at higher temperatures.
29. Which type of chromatography is often used for analyzing volatile compounds at high temperatures?
30. What is the purpose of the condenser in a distillation apparatus?
31. Which technique is used to separate a mixture of liquids with boiling points differing by more than 25°C?
32. A compound that sublimes readily is likely to have:
33. Which purification method is based on the principle of selective adsorption?
34. In column chromatography, the stationary phase is typically a solid adsorbent packed into a tube. The mobile phase is:
35. Differential extraction is most effective when the solute has a significantly different ______ in the two solvents.
36. Which of the following is NOT a type of chromatography?
37. What is the primary advantage of vacuum distillation?
38. Which chromatography technique uses a thin layer of adsorbent material coated on a glass plate?
39. In fractional distillation, the fractionating column provides a large surface area to facilitate:
40. Steam distillation is particularly useful for purifying compounds that are:
41. Which of the following is a common application of crystallization?
42. Sublimation is a process where a solid directly converts into:
43. Which chromatographic technique is used to separate ions based on their charge and size?
44. What is the mobile phase in paper chromatography?
45. In chromatography, the stationary phase is:
46. Differential extraction relies on the difference in the ______ of the solute in two immiscible solvents.
47. Which type of distillation is used to separate liquids with very close boiling points?
48. Distillation is primarily used to separate liquids with significant differences in their:
49. Which of the following compounds can be purified by sublimation?
50. What is the principle behind crystallization as a purification technique?