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Thursday, February 28

Chemistry Chapter # 2

Link to take the Online Test : Chemistry Chapter # 2 Part 1
Those who are unable to access the online test can see the questions written below. These are the same as those present in above link.

1. The process of filtration is used to
A. Separate the two miscible liquids
B. Separate the two immiscible liquids
C. Separate insoluble particles from liquids
D. Separate solute from solution

2. Fluted filter paper is used for
A. Filtering the hot saturated solution
B. To avoid premature crystallization of solute
C. Increasing the Rate of filtration
D. To dissolve large amount of substance

3. Sublimation is the process for the separation of
A. Solute and solvent from a solution
B. Solution of volatile and non-volatile liquids
C. Ionic and covalent compounds
D. Volatile and non-volatile solids

4. A method of separating a component from its solution according to distribution law is called :
A. Crystallization
B. Sublimation
C. Paper chromatography
D. Solvent extraction

5. A crucible made of porcelain, which has a perforated bottom with a filter paper cut to its size, is called ________ crucible
A. Lead
B. Paper
C. Gooch
D. Sintered Glass

6. Solid --> vapour, this is called
A. Sublimation
B. Condensation
C. Vaporization
D. Filtration

7. The process of separating solids or suspended particles from liquids by passing through a filter medium is called
A. Sublimation
B. Filtration
C. Condensation
D. Vaporization

8. The most common chromatography performed in a laboratory is _______ chromatography
A. Column
B. T.L.C
C. Paper
D. G.L.C

9. Which is the way to carry out chromatography?
A. Ascending
B. Descending
C. Radial
D. all of the above

10. In chromatography K stands for
A. Rate
B. Distribution coefficient
C. Rate law
D. Both A and B

11. The chromatography in which the fixed phase is solid is called _______ chromatography
A. Partition
B. Adsorption
C. Gas
D. none of these

12. The chromatography in which the fixed phase is liquid is called _______ chromatography
A. Adsorption
B. Partition
C. Gas
D. none of these

13. In paper chromatography the suspended paper is dipped about ______ mm
A. 3
B. 4
C. 10
D. 5

14. When iodine in aqueous layer (I3-1 ion) is transferred to CCl4 layer then the colour change is
A. Purple colour disappears & brown colour appears
B. Brown colour disappears & purple colour appears
C. Purple colour fades & green colour appears
D. Green colour changes to brown colour

15. Solids which have high vapour pressure at a temperature below their boiling point, when heated it start
A. Condensing
B. Decomposing
C. Melting
D. Sublimating

16. The tip of the funnel stem should touch the side of beaker because
A. Filtrate runs down without splashing
B. The filtrate is quick
C. This gives the medium sized crystals
D. This gives the bigger crystals

17. Sintered glass crucible is used for
A. Separation of two miscible liquids
B. Purification of solid
C. Avoid premature crystallization of solute
D. Convenient filtration than that by gooch crucible

18. The solvent is selected for crystallization of a substance on the basis of
A. Hit and trial method
B. It should react chemically
C. Its non-polar nature
D. Its polar nature

19. The meaning of ‘Khromatos’ is
A. Colourless
B. Colour forming
C. Colour writing
D. Colour spreading m

20. Solvent extraction method is particularly useful technique for separation, when product to be separated is
A. Volatile and thermally stable
B. Volatile and thermally unstable
C. non-Volatile and thermally stable
D. non-Volatile and thermally unstable

21. The different component (solutes) of the mixture are separated by paper chromatography due to
A. The amount of solvent taken in the tank
B. Temperature of the experiment
C. Size of the chromatography tank used
D. The different Rf values of solutes

22. The solvent which is added latter in solvent extraction is always
A. better
B. Bad
C. Same
D. reactive

23. Which one of the following methods will be used to separate the mixture of NaCl and sand?
A. Shake the mixture with water, filter and dry the substance on filter paper
B. Shake the mixture with water, filter & evaporate the filtrate
C. Shake the mixture & distilled off the liquid
D. Heat the mixture gently & collect the substance which melts

24. To achieve a good separation, the two liquids are gently shaken to increase the area of
A. Miscibility
B. Separation
C. Solubility
D. Contact

25. The value of Rf is always
A. between 1 and 0
B. less than 1
C. greater than 1
D. greater than 0

26. Different component of mixture have different Rf values due to
A. Their different co-efficient in the solvent
B. Polar solvent used
C. non Polar solvent used
D. Solvent front is lower than the spots of the solutes

27. A water insoluble organic compound is prepared by the reaction of salicylic acid with the mixture of acetic acid and acetic anhydride, which one of the following techniques will be used for the separation of aspirin?
A. Solvent extraction
B. Sublimation
C. Chromatography
D. Filtration

28. To prepare the medium size crystals, the hot filtrate is cooled
A. Fast
B. slowly
C. both a and b
D. moderately

29. A complete quantitative analysis consists if how many steps?
A. 3
B. 4
C. 2
D. 1

30. Chromatography is useful for
A. separation
B. isloation
C. purification
D. all of these

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