In a gas mixture of He, Ne, and Ar with a total pressure of 8.40 atm, the mole fraction of Ar is if the partial pressures of He and Ne are 1.50 and 2.00 atm, respectively.

1.71

Explanation:

According to Dalton's law, the total pressure is the sum of individual pressures.

Given :

= total pressure of gases = 8.40 atm

= partial pressure of helium = 1.50 atm

= partial pressure of neon = 2.00 atm

= partial pressure of argon = ?

putting in the values we get:

To calculate the vapor pressure of the solution, we use the law given by Dalton, which is:

We are given:

= partial pressure of argon = 4.90

= mole fraction of argon = ?

Putting values in above equation, we get:

Thus the mole fraction of Ar is 1.71