At identical temperature and pressure, the rate of diffusion of hydrogen gas is `3 sqrt( 3)` times that of a hydrocarbon having molecular formula `C_(n) H_(2n-2)`. What is the value of n ?

Options

A. 1
B. 4
C. 3
D. 8

Answer

B

Explanation

`(r_(H_(2)))/(r_("Hydrocarbon")) = sqrt((M_("Hydrocarbon"))/(M_(H_(2))) ) = 3sqrt(3)`
`:. sqrt((M_("Hydrocarbon"))/(2)) = 3 sqrt(3)`
`(M_("Hydrocarbon"))/(2) = 27`
`M_("Hydrocarbon") = 2 xx 27 = 54 `
`:. N = 4` and hydrocarbon is `C_(4) H_(6)`