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Percentage of Nitrogen in Air

The air we breathe is a mixture of many gases. While we rely on oxygen to survive, it is actually not the most abundant gas in the atmosphere.

Question (Click to Flip)

What is nitrogen fixation?

Answer

Nitrogen fixation is the process by which certain bacteria (like Rhizobium) convert atmospheric nitrogen gas into usable nitrogen compounds (like nitrates) in the soil, which plants can then absorb.

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Key Facts

Even though there is 78% nitrogen in the air we breathe, our bodies cannot use it directly. We breathe it in and breathe it right back out. We get the nitrogen our bodies need from the food we eat.

Composition of Air

The Earth's atmosphere is composed primarily of two gases:

  1. Nitrogen (N₂): 78% (Most abundant)
  2. Oxygen (O₂): 21%
  3. Argon (Ar): ~0.9%
  4. Carbon Dioxide (CO₂): ~0.04%
  5. Other gases (Neon, Helium, Methane, Water vapour): Trace amounts

Why is Nitrogen So Important?

  • Dilutes Oxygen: If the air was 100% oxygen, fires would burn out of control and it would be toxic to humans. Nitrogen dilutes oxygen to a safe level.
  • Plant Growth: Nitrogen is a crucial component of amino acids and proteins. Plants need it to grow, which they get from the soil (through nitrogen fixation by bacteria), not directly from the air.
  • Food Packaging: Nitrogen gas is pumped into chips and snack packets to prevent the food from spoiling (oxidation) and to keep it crisp.

Questions and Answers

What is nitrogen fixation?+

Nitrogen fixation is the process by which certain bacteria (like Rhizobium) convert atmospheric nitrogen gas into usable nitrogen compounds (like nitrates) in the soil, which plants can then absorb.

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