# How do you calculate the partial pressure of oxygen in the air?

Jul 26, 2017

#### Answer:

It is proportional to its molar composition in the atmosphere.

#### Explanation:

Partial pressure is the component of a total pressure exerted by a single compound. It is proportional to the molar composition of the atmosphere.

For an atmospheric pressure of 100kPa and an estimated average oxygen content in air of 21%, the partial pressure of oxygen would be:

0.21 * 100 = 21kPa