What is the primary gas found in the Earth's atmosphere?

The primary gas found in the Earth's atmosphere is nitrogen, which constitutes about 78% of the atmosphere by volume. Nitrogen is a colorless, odorless gas that plays several important roles in maintaining the stability of the atmosphere and supporting life. Although oxygen is essential for the survival of many organisms and makes up about 21% of the atmosphere, nitrogen is significantly more abundant. This abundance of nitrogen helps dilute the oxygen and prevents rapid combustion, providing a stable environment conducive to life. Carbon dioxide and argon, while important in their own right, make up only a minor fraction of the atmosphere, with carbon dioxide being around 0.04% and argon approximately 0.93%. Therefore, nitrogen is correctly identified as the primary gas in the Earth’s atmosphere.