Which component makes up the majority of Earth's atmosphere?

Nitrogen makes up the majority of Earth's atmosphere, constituting about 78% of it. This gas is essential for various biological processes, including the nitrogen cycle, which is crucial for plant growth and ecosystem sustainability. Nitrogen is inert, meaning it does not easily react with other substances, allowing it to act as a stable background gas in the atmosphere.

The significance of nitrogen's abundance is reflected in its role in the atmosphere, where it serves to dilute oxygen and other gases, thereby contributing to the overall balance needed for life on Earth. Additionally, this large proportion of nitrogen helps to moderate temperature changes, playing a part in maintaining the atmosphere's stability.