Question

The rate of diffusion of methane is twice that of X. The molecular mass of X is

• A. 16
• B. 32
• C. 80
• D. 64

Answer 1

Answer: (D)

64

Answer 2

$r_{methane}$2 a (say), $r_x$ - a
$\frac{r_{methane}}{r_X}= \sqrt{\frac{M_X}{M_{methane}}}$
$\frac{2a}{a} = \sqrt{\frac{M_x}{16}}$
$\frac{M_x}{16}$ = 4 or $M_x$ = 64