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General Knowledge :: Chemistry

  1. The first metal used by man was

  2. A.

     iron

    B.

     copper

    C.

     gold

    D.

     bronze


  3. The hydronium ion is

  4. A.

     H+

    B.

     HO -

    C.

     H2+

    D.

     H3O+


  5. The most electropositive elements among the following is

  6. A.

     Na

    B.

     Ca

    C.

     K

    D.

     Cs


  7. The method that cannot be used for removing permanent hardness of water is

  8. A.

     adding sodium carbonate

    B.

     distillation

    C.

     adding caustic soda

    D.

     boiling


  9. The following are the half lives of four active isotopes. Which one of the following is the most dangerous to handle?

  10. A.

     3 billion years

    B.

     100 years

    C.

     0.01 minute

    D.

     13 days


  11. The gas used for artificial ripening of green fruit is

  12. A.

     ethylene

    B.

     ethane

    C.

     carbon dioxide

    D.

     acetylene


  13. Zone refining is used for the purification of

  14. A.

     Au

    B.

     Ge

    C.

     Ag

    D.

     Cu


  15. The main chemical constituent of the oil of cardamom which is responsible for flavour of this oil is

  16. A.

     cineole

    B.

     engenol

    C.

     geraniol

    D.

     limonene


  17. The molecule which has the highest percentage of ionic character among the following is

  18. A.

     HI

    B.

     HF

    C.

     HCI

    D.

     HBr


  19. The high reactivity of fluorine is due to

  20. A.

     its high electro negativity

    B.

     small size of fluorine atom

    C.

     availability of d-orbitals

    D.

     strong F - F bond