Question

The pressure of a mixture of equal weight of two gases of mol wt. 4 and 40, is 1 atm. The partial pressure of the lighter gas in this mixture is

• A. 0.55 atm
• B. 0.1 atm
• C. 1 atm
• D. 0.11 atm

Answer 1

Answer: (C)

1 atm

Answer 2

The partial pressure of the lighter gas = mole fraction $\times$ total pressure = $\frac{W/4}{W/4 + W/40} \times$ 1.1 = 1 atm