Two gas bulbs are connected by a thin tube. Calaculate the partial pressure of helium after the connective value is opened at a constant temperature of `27^(@)C`

Options

A. 1 atm
B. `0.328 atm`
C. `1.64 atm`
D. `0.166 atm`

Answer

D

Explanation

`n_(He) = (PV)/(RT) = (0.63 xx 1.2)/(0.0821 xx 300) = 0.03`
`n_(Ne) = (2.8 xx 3.4)/(0.0821 xx 300) = 0.39`
`x_(He) = (n_(He))/(n_(He) + n_(Ne)) = (0.03)/(0.03 + 0.39) = 0.0714`
Total pressure after connecting the bulbs will be :
`P_(1)V_(1) + P_(2) V_(2) = P_(R) (V_(1) + V_(2))`
`0.63 xx 1.2 + 2.8 xx 3.4 = P_(R) (1.2 + 3.4)`
`P_(R) = 2.33 atm`
`P_(He) = x_(He) xx P_(R) = 0.0714 xx 2.33 = 0.166 atm`