A vessel contains a mixture of equal masses of helium and oxygen at a pressure of 600 torr. Calculate the partial pressures of components in the mixture.

Explanation

Let the mass of each component gas is x.
Total number of moles in the mixture `= ("xg of He")/(4g " of " mol^(-1)) + ( xg " of " O_2)/( 32 g " of " mol^(-1))= ( 9x)/( 32 g mol^(-1))`
Partial pressure = pressure of the mixture x mole fraction Partial pressure of He`= 600 xx ( x//4)/( 9x //32 ) = 600 xx (8)/(9) `
`=533.33 ` torr
Partial pressure of `O_2 = 600 xx (x //32)/( 9x //32) = 600 xx (8)/(9)`
`=66.67 ` torr
(or) Partial pressure of `O_2 =600-533.37 = 66.67` torr