If the partial pressure of oxygen in a scuba air tank is 73.44 atm, the partial pressure of nitrogen is 128.52 atm, and the partial pressure of other gases is 2.04 atm, what is the percent composition of the air mixture in the scuba tank?

To answer this, we use Raoult's Law where the partial pressure is equal to the product of the fraction of the gas in the mixture and its total pressure. Also, we use Dalton's Law of Partial Pressure where the total pressure is equal to the sum of the partial pressure of the gases in the mixture.

Ptotal = 73.44 + 128.52 + 2.04 = 204 atm

201.96 = x (204)

x = 0.99