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General Knowledge :: Chemistry

  1. Ozone layer of atmosphere absorbs:

  2. A.

     Ultraviolet rays

    B.

     Infra-red rays

    C.

     All radiations of Light

    D.

     Cosmic rays.


  3. Air shows the property of

  4. A.

     N2

    B.

     O2

    C.

     Both A and B

    D.

     None of these


  5. The most abundant constituent of atmospheric air is :

  6. A.

     Carbon

    B.

     Hydrogen

    C.

     Oxygen

    D.

     Nitrogen


  7. The percentage of oxygen in air is approximately

  8. A.

     100%

    B.

     1%

    C.

     78%

    D.

     21%


  9. The major constituent of air is

  10. A.

     Nitrogen

    B.

     Carbon dioxide

    C.

     Oxygen

    D.

     Hydrogen


  11. Air is said to be saturated when :

  12. A.

     It contains maximum content of water vapour

    B.

     Its pressure is minimum

    C.

     Its thickness is maximum

    D.

     It blows over the barren land


  13. For extinguishing fire, we use

  14. A.

     Hydrogen

    B.

     Carbon Monoxide

    C.

     Carbon Dioxide

    D.

     Marsh gas


  15. Dry powder fire extinguishers contain

  16. A.

     Sand

    B.

     Sand and sodium carbonate

    C.

     Sand and potassium carbonate

    D.

     Sand and sodium bicarbonate


  17. Dry ice is the solid form of :

  18. A.

     Air

    B.

     Carbon dioxide

    C.

     Nitrogen

    D.

     Water


  19. Diamonds are glittering and attractive because light incident on them undergoes

  20. A.

     Highest refraction

    B.

     Multiple internal reflections

    C.

     Multiple surface reflections

    D.

     Hundred percent transmission