1. Oxygen gas (O2):
- This is the most common form of oxygen, making up about 21% of Earth's atmosphere.
- It is composed of two oxygen atoms covalently bonded together.
- Oxygen gas is colorless, odorless, and tasteless at standard temperature and pressure.
- It is essential for respiration in most organisms.
2. Ozone (O3):
- Ozone is a less common form of oxygen that is found in small amounts in the Earth's atmosphere, mainly in the stratosphere.
- It is composed of three oxygen atoms covalently bonded together.
- Ozone is a pale blue gas with a pungent odor.
- It is produced naturally by the interaction of sunlight with oxygen molecules in the atmosphere and also as a byproduct of certain chemical reactions.
- Ozone plays an important role in protecting the Earth's surface from harmful ultraviolet (UV) radiation from the sun.
