Equal weights of two gases of molecular weight 4 and 40 are mixed. The pressure of the mixture is 1.1 atm. The partial pressure of the light gas in this mixture is

Options

A. 0.55 atm
B. 0.11 atm
C. 1 atm
D. 0.12 atm

Answer

C

Explanation

No. of moles of lighter gas `= (m)/(4)`
No. of moles of heavier gas `=(m)/(40)`
Total no. of moles of `(m)/(4)+(m)/(40)=(11m)/(40)`
Mole fraction of lighter gas `((m)/(4))/((11m)/(40))=(10)/(11)`
Partial pressure due to lighter gas `=P_(o)xx(10)/(11)=1.1 xx (10)/(11) =1 `atm.