Percentage of oxygen in air

Answer 1

Oxygen comprises about 21% of fresh air. Room air is nearly always refreshed from outsides sources sufficiently fast for this value to hold true. However, if ventilation is extremely poor it can differ.

Answer 2

Percentage is percentage and weight is weight.

Of the air that fills a room, about 20% is Oxygen, about 75% is Nitrogen, about 4% is Carbon Dioxide and small proportions of other gasses.

Answer 3

Oxygen makes up about 21% of the Earth's atmosphere. Nitrogen is the most abundant gas, making up approximately 78%. Other gases like argon, carbon dioxide, and trace gases make up the rest.

Answer 4

Our atmosphere is made up of 78% Nitrogen, 21% O2 Or Oxygen, and 1% other gases.

Answer 5

Accoding to atmospherical balance 21% of oxygen is available in atmosphere.

Answer 6

Normally Oxygen comprises 20% of the air.

Answer 7

Twenty percent of it is air is oxygen

Answer 8

20.95% of the air we breath is Oxygen.

Answer 9

21 percent

Answer 10

20.95%