| 1 |
Which one is not example of a sublimate. |
- A. NH4Cl
- B. I
- C. NaCl
- D. Benzoic Acid
|
| 2 |
Safe and reliable method of drying crystals is through. |
- A. Pressing it between folds of filter paper
- B. Drying it in oven
- C. Evaporation of solution
- D. Vacuum desiccator
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| 3 |
Gooch crucible is made of. |
- A. Glass
- B. Paper
- C. Teflon
- D. Procelain
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| 4 |
Which one of the following methods will be used to separate the mixture of NaCl and sand. |
- A. Chromatography
- B. Solvent extraction
- C. Sublimation
- D. Filtration
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| 5 |
To achieve a good separation, the two liquids are gently shaken to increase their area of. |
- A. Miscibility
- B. Separation
- C. contact
- D. Solubility
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| 6 |
Solvent extraction method is a particularly useful technique for separation when the product to be separated is. |
- A. Non volatile or thermally unstable
- B. Volatile or thermally stable
- C. Non volatile or thermally stable
- D. Volatile or thermally unstable
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| 7 |
During the process of crystallization, the hot saturated solution; |
- A. Is cooled very slowly to get large-sized crystals
- B. Is cooled at a moderated rate to get medium-sized crystals
- C. Is evaporated to get the crystals of the product
- D. Is mixed with an immiscible liquid to get the pure crystals of the produce
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| 8 |
The crystallization of a solid substance is done from a hot saturated solution. The solution is |
- A. Evaporated rapidly
- B. Cooled very slowly to get good crystals
- C. Cooled rapidly to get excellent crystals
- D. Mixed with another miscible solvent
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| 9 |
The comparative rates at which the solutes move in paper chromatography depend on. |
- A. The size of paper used
- B. Rf values of solutes
- C. Temperature of the experiment
- D. Size of the chromatographic tank used
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| 10 |
Which one of the following substances is not used as drying agent in desiccators. |
- A. Calcium chloride
- B. Phosphorus pentoxide
- C. Silica gel
- D. 50% NaCl
|