The Graham's law states that ''at constant pressure and temperature the rate of diffusion or effusion of a gas is inversely proportional to the squar root of its density Rate of diffusion `prop (1)/(sqrt(d))`
If `r_(1)` and `r_(2)` represent the rates of diffusion of two gases and `d_(1)` and `d_(2)` are their respective densities, then
`r_(1)/(r_(2))=sqrt((d_(2))/(d_(1)))`
`r_(1)/(r_(2)) =sqrt((M_(2))/(M_(1))) xx P_(1)/(P_(2))`
`(V_(1)xxt_(2))/(V_(2)xxt_(1)) = sqrt((d_(2))/(d_(1))) = sqrt((M_(2))/(M_(1)))`
`V prop n` (where n is no of moles)
`V_(1) prop n_(1)` and `V_(2) prop n_(2)`
Helium and argon monoatomic gases and their atomic weights are 4 and 40 respectively Under identical conditions helium will diffuse through a semipermeable membrane .

Options

A. `3.16` time as fast as argon
B. `7.32` time as fast as argon
C. `1.58` time as fast as argon
D. `10` time as fast as argon

Explanation

`(r_(He))/(r_(Ar)) =sqrt((M_(Ar))/(M_(He)))= sqrt((40)/(4)) =sqrt10 = 3.16`
`{:(Givenreaction:,2H_(2)+,O_(2)rarr,2H_(2)O,),("Vbeforereaction",1,1,0,),(Vafterreaction(i nL),0,0.5,1,):}` .