Mondo Knows Facts
Nitrogen and oxygen make up ninety-nine percent of dry air
Dry atmospheric air consists of 78 percent nitrogen and 21 percent oxygen by volume
Earth's atmosphere is composed primarily of diatomic nitrogen gas, which accounts for roughly 78 percent of dry air volume, and diatomic oxygen, which accounts for 21 percent. Argon makes up most of the remaining 1 percent, with trace gases like carbon dioxide and water vapour filling the rest. This unique balance supports life while suppressing uncontrolled combustion.
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Tags: earth science, atmosphere, air
Nitrogen and oxygen make up ninety-nine percent of dry air: the short answers
- Where does this come from, and can I check it?
- Dry atmospheric air consists of 78 percent nitrogen and 21 percent oxygen by volume. The figure is taken from NOAA, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
- Is this really a science fact?
- Yes. It sits on the Science shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
- What else can I read about it?
- The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.