Teacher Training Curriculum on Environmental Issues | Seite 30

water source without damaging the environment.
Step 5: Replace the water and wash off the oil from the bowl before replacing it with fresh water
from the tap. Now fix a new slick with 20 new drops of oil. Take a teaspoon of calcium oxide (CaO)
and sprinkle it on the stain. (Chemical clean-up process)
Where are the oil slicks?

What are the effects of a chemical clean-up like this on the fauna and the flora on the seabed?

6) Fixing a new oil slick on the water by dropping another 20 drops more of oil. Now pour 20 drops
of liquid soap on to the oil slick (The method is called dispersion)
- What happens to the oil?

Detergents dispersed the oil slicks by breaking them up into finer fragments but they still exist in
the water.
7) Now try to wash the feather with soap. How do you manage it?

8) Can you now describe why the birds that come in contact with oil in the sea or other water
sources have it so difficult to survive?

9) Wash off the bowl. Notice how difficult it is to remove the oil from the bowl. Remember that the
oil you are using is vegetable oil. How difficult will it be if it had been crude oil which is several
times thicker than the cooking oil?

Answer all the questions and write your name on the paper and hand it to me. :) :) :)
Remember that everything should be NEAT AND TIDY BEFORE YOU LEAVE THE
CLASSROOM.

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