Testing

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The Earth

MC Question

 

1. Why can gases in air be separated by fractional distillation of liquid air?
   1.   The gases have different boiling points.
   2.   The gases have different melting points.
   3.   The gases have different chemical properties.
   4.   The gases have different percentages in air by volume.
2. What colour can be observed when a sample of sodium chloride solid is heated in a Bunsen flame?
   1.   Blue
   2.   Golden Yellow
   3.   Green
   4.   Lilac
3. Which of the following gas(es) is/ are least likely to be found in air?
   
   1.   Nitrogen
   2.   Noble gases
   3.   Hydrogen
   4.   Carbon dioxide
4. Which of the following substances is the most abundant in dry air?
   1.   Methane
   2.   Oxygen
   3.   Carbon Dioxide
   4.   Nitrogen
5. What colour can be observed when a sample of limestone is heated in a Bunsen flame?
   1.   Lilac
   2.   Brick red
   3.   Blue
   4.   Green
6. We test oxygen with (X), the expected observation is (Y)
   1.   X : acidfided potassium permanganate solution
      Y : the solution changes to colourless
   2.   X : a glowing splint
      Y : the glowing splint relights
   3.   X : lime water
      Y : the solution turns milky
   4.   X : damp blue litmus paper
      Y : the paper turn red and then white
7. Which of the following statements is correct?
   (1) Air is a mixture of two gases, nitrogen and oxygen.
   (2) The gases in air are highly unreactive.
   (3) The composition of air may vary slightly from time to time.
   1.   (1) only
   2.   (3) only
   3.   (1) and (3) only
   4.   (2) and (3) only
8. Which of the following is the correct procedure to change calcium carbonate to limewater?
   1.   Heating strongly, adding water, and then filtering off the solid suspension.
   2.   Heating with plenty of water and then leave it for a few minutes
   3.   Heating and then adding in plenty of dilute acid.
   4.   Adding plenty of water with carbon dioxide and then heating.
9. 
   Consider the experimental set-up above, Which of the following combinations concerning the functions of X and Y is correct?
   1.   X:To speed up distillation
      Y:To condense vapour
   2.   X:To ensure even boiling
      Y:To condense vapour
   3.   X:To speed up distillation
      Y:To remove impurities
   4.   X:To ensure even boiling
      Y:To remove impurities
10. A student wants to prepare a crystal of sodium chloride. He/she first heats a solution of sodium chloride to boil some water away. Which of the following procedures can be used to check whether the solution is concentrated enough for crystallization?
    1.   Taste it.
    2.   Observe if the solution is mliky.
    3.   Dip a glass rod into the solution, take it out to see if small crystals appear on the rod.
    4.   Measure the volume of the solution to see if it is half of the initial volume.
11. Which of the following arrangements enhances the cooling effect of Liebig condenser in a distillation set-up?
    1.   Water remains stagnant in the Liebig condenser.
    2.   Water runs downwards across the Liebig condenser.
    3.   Water runs upwards across the Liebig condenser.
    4.   Water runs up and down repeatedly across the Liebig condenser.
12. Which of the following substances will NOT be obtained in the electrolysis of sea water?
    1.   Hydrogen
    2.   Sodium hydroxide
    3.   Oxygen
    4.   Chlorine
13. Which of the following elements can be identified easily by flame test?
    1.   Nitrogen
    2.   Potassium
    3.   Chlorine
    4.   Oxygen
14. When marble is heated, a gas is evolved. Which of the following statements concerning the gas evolved is correct?
    1.   The gas is pale green in colour.
    2.   The gas relights a glowing splint.
    3.   The gas turns limewater milky.
    4.   The gas turns bromine water colourless.
15. Which of the following is the industrial method of manufacturing oxygen?
    1.   Electrolysis of water
    2.   Fractional distillation of liquid air
    3.   Photosynthesis
    4.   Heating silver oxide
16. Which of the following is NOT a common use of carbon dioxide?
    1.   It can be used to make fire extinguishers.
    2.   It is put into soft drinks.
    3.   It is used to fill light bulbs.
    4.   It is used as a refrigerant.
17. When acidified silver nitrate solution is added to magnesium chloride solution, a white precipitate is formed. The white precipitate is
    1.   magnesium nitrate
    2.   silver chloride
    3.   silver
    4.   magnesium
18. Which of the following statements about sea water is correct?
    1.   It turns a dry blue cobalt chloride paper pink.
    2.   It turns a dry pink cobalt chloride paper blue.
    3.   It turns a moist pink cobalt chloride paper blue.
    4.   It turns a moist blue cobalt chloride paper pink.
19. Which of the following concerning nitrogen is INCORRECT?
    (1) It is flammable.
    (2) It is a liquid at room temperature.
    (3) It is the most abundant component in the Earth atmosphere.
    1.   (1) and (2) only
    2.   (1) and (3) only
    3.   (2) and (3) only
    4.   (1), (2) and (3)
20. Who am I?
    1.   FY
    2.   MY
    3.   BY
    4.   GA

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