Question

Which two forms of oxygen are found in the atmosphere and why it is essential?

[3 Marks]
[Oxygen Cycle]

Answer 1

Solution:

• Elemental oxygen is normally found in the form of a diatomic molecule. However, in the upper regions of the atmosphere, a molecule containing three atoms of oxygen is found, which is called ozone. [ 1 Mark]
• The presence of oxygen in the air (atmosphere) is essential for the following:

1. The life processes such as respiration, in all living organisms.
2. Combustion of fuels.

[ 1 Mark]

• The presence of ozone in the air (atmosphere) is essential for the following:

1. Ozone is a gas in the atmosphere that guards all living things on Earth from the Sun's harmful ultraviolet (UV) rays.

[1 Mark]