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General Knowledge :: Chemistry

  1. What is the mass percentage of oxygen in carbon dioxide (CO2)?

  2. A.

     30.5%

    B.

     50.9 %

    C.

     65.8 %

    D.

     72.7 %


  3. Number of 6.023 × 1023 atoms present in one mole of a gas at STP is

  4. A.

     6.023 × 1020

    B.

     6.023 × 1023

    C.

     6.023 × 10–20

    D.

     6.023 × 10–23


  5. The percentage of nitrogen present in ammonium sulphate is :

  6. A.

     27%

    B.

     25%

    C.

     30.5%

    D.

     18%


  7. The value of Avogadro Number is

  8. A.

     6.023 × 1022

    B.

     6.023 × 1023

    C.

     6.023 × 1024

    D.

     6.023 × 1025


  9. Aqua regia is a 1 : 3 mixture, by volume, of

  10. A.

     Conc. nitric acid and conc. hydrochloric acid

    B.

     Conc. hydrochloric acid and conc. nitric acid

    C.

     Conc. nitric acid and conc. sulphuric acid

    D.

     Conc. sulphuric acid and conc. nitric acid


  11. Gold dissolves in

  12. A.

     Hydrochloric acid

    B.

     Nitric acid

    C.

     Aqua regia

    D.

     Acetic acid


  13. Nitric acid does not react with

  14. A.

     Gold

    B.

     Copper

    C.

     Zinc

    D.

     Iron


  15. Nitrogen in water is commonly found in the form of

  16. A.

     Nitrous oxide

    B.

     Nitrate

    C.

     Nitric oxide

    D.

     Nitrite


  17. Aquaregia is a mixture of the following in the ratio 1 : 3 by volume

  18. A.

     Conc. HNOand conc. HCl

    B.

     Conc. HNOand conc. H2SO4

    C.

     Dil. HCl and dil. HNO3

    D.

     Conc. HCl and conc. HNO3


  19. One of the following is used to dissolve noble metals. That is

  20. A.

     Nitric acid

    B.

     Hydrochloric acid

    C.

     Sulphuric acid

    D.

     Aqua regia