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Chemistry - Separation technique

 1. Which one of the following is NOT a mixture?

A. Air

B. Sugar

C. Paint

D.  Crude oil


2. Oil and water may be separated by using?

A. a separating funnel

B. a Liebig condenser

C. chromatography paper

D. a filter funnel


3. Air is a mixture of

A. liquids

B. solids

C. gases

D. liquids and gases


4. In a coffee machine, the ground coffee is separated from the coffee solution by using

A. toilet paper

B. filter paper

C. sand paper

D. tissue paper


5. Which one of the following techniques would best be used to separate soil and water?

A. Decanting

B. Filtration

C. Fractional distillation

D. Chromatography


6. This is a simple method of separating an insoluble solid from a liquid.

 A. Filtration

 B.  Distillation

 C. Evaporation

 D. Decantation


7. In the process of evaporation, which one of the following pieces of laboratory apparatus would NOT be used?

 A. wire gauze

 B. evaporating basin

 C. filter funnel

 D bunsen burner


8. Which one of the following is a disadvantage of evaporation?

A. It always requires heat

B. It cannot be used for insoluble solids

C. The solvent is not recovered

D. All of the solute is recovered


9. Water and alcohol are easily separated by distillation because of their?

 A. different densities

 B. different boiling points

 C. different melting points

 D. different colours


10. Two changes of state occur during distillation.

What are these changes of state?

 A. Liquid to gas and gas to solid

 B. Solid to gas and gas to liquid

 C.  Liquid to gas and gas to liquid

 D. Solid to liquid and liquid to gas


11. Which of the following pairs of substances may best be separated through distillation?

 A. water and soil

 B. water and alcohol

 C. sand and soil

 D. salt and sand


12. A magnet could be used to separate

 A. colours in a food dye

 B. water and sand

 C. sand and salt

 D.  sand and iron filings


13. Evaporation is used to

 A. separate the dyes in a marker

 B.  obtain the solute from the solution

 C. separate liquids of different boiling points

 D.  separate solids of different particle size


14. Sodium chloride can be separated from rock salt by first adding water to the mixture to dissolve the sodium chloride. The separation then takes place in two stages:

 A.  filtration followed by evaporation

 B.  filtration followed by decanting

 C. distillation followed by decanting

 D.  evaporation followed by filtration


15. The separation technique involving the use of filter paper, the substance left in the filter paper is called?

A. filtrate

B. Solution

C. Residue

D. distillate



Answers:

1. B

2. A

3. C

4. B

5. B

6. D

7. C

8. C

9. B

10. C

11. B

12. D

13. B

14. A

15. C

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