Chemical reaction and equations worksheet-1

Chemical reaction and equations worksheet-1

 

Fill in the Blanks:

  1. CO2(s) → CO2(g) is a __________ change.

  2. Water evaporates from the surface of the ocean. It is a _________change.

  3. Change in odor, or color is a_______ change.

  4. Rusting is a__________ change.

  5. Cutting of trees is a__________ change.

  6. Rusting of iron occurs due to __________.(Oxidation/reduction)

  7. The balanced equation has __________ molecules of water.

  8. The balanced equation has ________ molecules of Aluminium hydroxide.

  9. This is a _______ reaction.

  10. _________ is oxidized.

  11. Reduction is _______ of electron.

  12. Reducing agent is one which _______ electrons.

  13. Gold and platinum do not corrode in moist air as they are ______ reactive.

  14. The names of CO32– is__________  .

  15. The name of SO42– is__________

  16. The name of (COO)22– is__________

  17. Calcium hydroxide + carbon di-oxide → __________ + Water

  18. Zn + CuSO4 → ZnSO4 + CU(s), is an example of _________reaction.

  19. In Corrosion iron is oxidized by oxygen of air in the presence of moisture forming ________.

  20. Silver quickly acquires a thin black layer of __________.

 

Answer keys:

  1. Physical or Physical change

  2. Physical or Physical change

  3. Chemical or Chemical change

  4. Chemical or Chemical change

  5. Physical or Physical change

  6. Oxidation

  7. 2

  8. 1

  9. Displacement

  10. Carbon mono-oxide

  11. Gain

  12. Looses

  13. Less

  14. carbonate ion

  15. sulphate ion

  16. oxalate ion

  17. Calcium carbonate

  18. Displacement

  19. Hydrated iron oxide

  20. silver sulphide