< b="" />Air is a mixture of< />

Air is a mixture of several gases, and the composition of air can vary slightly depending on the location and environmental factors. However, the major components of air are nitrogen, oxygen, carbon dioxide, and water vapor.

< b="" />Option B: Nitrogen, Oxygen, Carbon Dioxide, Water Vapor< />

The correct answer is Option B, which states that air is a mixture of nitrogen, oxygen, carbon dioxide, and water vapor. Let's understand the role of each component in the air.

1. < b="" />Nitrogen< />:
- Nitrogen is the most abundant gas in the Earth's atmosphere, making up around 78% of the total volume of air.
- It is a colorless and odorless gas that is essential for the growth and development of plants.
- Nitrogen is also used in various industrial processes, such as in the production of ammonia for fertilizers and in the manufacturing of electronics.

2. < b="" />Oxygen< />:
- Oxygen is the second most abundant gas in the atmosphere, accounting for approximately 21% of the air.
- It is a colorless and odorless gas that is vital for the survival of most living organisms, including humans.
- Oxygen is necessary for cellular respiration, the process by which organisms convert food into energy.
- It is also used in various industrial applications, such as in the production of steel and in medical treatments.

3. < b="" />Carbon Dioxide< />:
- Carbon dioxide is present in the air in relatively small quantities, usually around 0.04%.
- It is a greenhouse gas that plays a crucial role in the Earth's climate system.
- Carbon dioxide is released into the atmosphere through natural processes like respiration and volcanic activity, as well as human activities like burning fossil fuels.
- It is absorbed by plants during photosynthesis and is an essential component of the carbon cycle.

4. < b="" />Water Vapor< />:
- Water vapor is the gaseous form of water and is present in the air in varying amounts.
- It is an important component of the Earth's water cycle, where water evaporates from the surface, condenses into clouds, and eventually falls back to the ground as precipitation.
- Water vapor plays a crucial role in weather patterns and helps regulate the Earth's temperature.

In conclusion, air is a mixture of several gases, with nitrogen and oxygen being the main components. Carbon dioxide and water vapor are present in smaller amounts but still play significant roles in the Earth's atmosphere and climate system.

Air is made up of 78.09% nitrogen, 20.95% oxygen, 0.04% carbon dioxide, water vapours and other gases in meager amounts.