Available Answers

1. 1.

   Why do air bubbles come out when soil is added to water?

2. 2.

   Why is the presence of air in the soil essential for plants?

3. 3.

   Name two elements and two compounds which are present in air.

4. 4.

   Name two major components of air and their approximate proportions.

5. 5.

   Is the composition of air strictly fixed?

6. 6.

   Where would you expect a higher proportion of carbon dioxide in air?