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The approximate percent of oxygen in Earth's lower atmosphere is around 20.95% by volume.
the percentage of oxygen in the atmosphere today is about 20.95%. Or... if you round it you get the most common answer of 21%.
Oxygen makes up about 21% of Earth's lower atmosphere by volume.
The approximate percentage of oxygen in Earth's lower atmosphere is around 21% by volume.
21% of the atmosphere is oxygen.
Oxygen forms 21 percent of the Earth's atmosphere.
Oxygen is the gas that makes up about 21 percent of the Earth's atmosphere.
The mass percent of oxygen is approximately 21% in Earth's atmosphere.
Air is 20.5 percent oxygen.
Nitrogen. Oxygen makes up approximately 21% of the Earth's atmosphere, while nitrogen makes up about 78%. Together, they account for the vast majority of the gases present in the atmosphere.
About 21 of the Earth's atmosphere is made up of oxygen.
Oxygen accumulates in Earth's atmosphere from photosynthesis, where plants and algae convert carbon dioxide into oxygen. This process started with the emergence of photosynthetic organisms around 2.5 billion years ago, gradually increasing oxygen levels to the current 21 percent.