The most abundant gas in the Earth’s atmosphere is nitrogen, which makes up about 78% of the air we breathe.
Nitrogen is a colorless, odorless gas that is essential for life. It is a major component of proteins and nucleic acids, which are vital to all living organisms. While nitrogen itself is not directly usable by most living things, it plays a critical role in the nitrogen cycle, where it is converted into forms that plants and animals can absorb and use.
In contrast, the second most abundant gas is oxygen, which accounts for about 21% of the atmosphere. Oxygen is essential for the respiration of most living organisms and is produced through photosynthesis by plants.
The remaining 1% of the atmosphere comprises trace gases, including argon, carbon dioxide, and others. Understanding the composition of the atmosphere is crucial for studying environmental changes and the impacts of human activities.