At identical temperatures, the rms speed of hydrogen molecules is `4` times that for oxygen molecules. In a mixture of these in mass ratio `H_(2) : O_(2) = 1 : 8`, the rms speed of all molecules in n times the rms speed for `O_(2)` molecules, where n is

Options

A. `3`
B. `4//3`
C. `(8//3)^(1//2)`
D. `(11)^(1//2)`

Answer

D

Explanation

Moluclar number ratio is `H_(2) : O_(2) = 2/3 : 1/3`
That gives `(C_(rms))^(2) = 16(2/3)+1(1/3)` times the value for `O_(2)`.