Question

Trimix is a mixture of helium, nitrogen and oxygen. If a tank of Trimix has a total
pressure of 204 atm. and a partial pressure of helium of 143 atm, what is the mole
percent of He in the mixture?

Answer 1

The mole percent of He in the mixture is found by using following formula:

$\chi_{He}= \frac {P_{He}}{P_{total}} \cdot 100$%

$\chi_{He}= \frac {143 \space atm}{204 \space atm} \cdot 100$ % = 70.1 %