# How would you explain the partial pressure of oxygen?

May 19, 2018

In what scenario....?

#### Explanation:

Atmospheric pressure, $1 \cdot a t m$, is the sum of the individual partial pressures...

$1 \cdot a t m = 760 \cdot m m \cdot H g = \sum \left({P}_{{N}_{2}} + {P}_{{O}_{2}} + {P}_{\text{other gases}}\right)$

This is another restatement of old $\text{Dalton's Law of partial Pressures}$....

For the air we breathe now, ${P}_{{O}_{2}} = 160 \cdot m m \cdot H g$...and ${P}_{{N}_{2}} = 500 \cdot m m \cdot H g$ to a first approx...

For the relation between partial pressure and mole fraction, see here.