Which element has the highest percentage in the Earth's atmosphere?

Which element has the highest percentage in the Earth's atmosphere?

• A. Oxygen
• B. Nitrogen
• C. Carbon Dioxide
• D. Argon

Answer: (B)

Nitrogen is the most abundant gas in the Earth's atmosphere, making up about 78% of its composition. This significant presence plays a critical role in various atmospheric processes, including the nitrogen cycle, which is essential for life on Earth. Nitrogen is a key component of proteins and nucleic acids, vital for the growth and reproduction of living organisms. In contrast, oxygen, while crucial for respiration and combustion, constitutes roughly 21% of the atmosphere. Carbon dioxide, although important for photosynthesis and as a greenhouse gas, is present in only about 0.04%. Argon is even less abundant, comprising about 0.93% of the atmosphere. Thus, nitrogen's dominance in the atmospheric composition reflects its fundamental importance in the biological and chemical processes that sustain life.

Nitrogen is the most abundant gas in the Earth's atmosphere, making up about 78% of its composition. This significant presence plays a critical role in various atmospheric processes, including the nitrogen cycle, which is essential for life on Earth. Nitrogen is a key component of proteins and nucleic acids, vital for the growth and reproduction of living organisms.

In contrast, oxygen, while crucial for respiration and combustion, constitutes roughly 21% of the atmosphere. Carbon dioxide, although important for photosynthesis and as a greenhouse gas, is present in only about 0.04%. Argon is even less abundant, comprising about 0.93% of the atmosphere. Thus, nitrogen's dominance in the atmospheric composition reflects its fundamental importance in the biological and chemical processes that sustain life.