What is the primary component of Earth's atmosphere?

The primary component of Earth's atmosphere is nitrogen, which makes up approximately 78% of the atmosphere by volume. This high concentration of nitrogen plays a crucial role in maintaining the stability and chemical balance of the atmosphere. Nitrogen is a relatively inert gas, which means it does not readily react with other substances under normal conditions, contributing to the overall stability of the atmosphere.

While oxygen is essential for life as it supports combustion and respiration, it constitutes about 21% of the atmosphere. Carbon dioxide and argon are present in much smaller quantities, with carbon dioxide making up around 0.04% and argon around 0.93%. The significant presence of nitrogen compared to these other gases underlines its status as the primary component of the atmosphere.