Question

Hydrogen diffuses 6 times faster than gas X. The molecular mass for X will be___.

• A. 72
• B. 140
• C. 144
• D. 100

Answer 1

The correct option is A

72

$\frac{r_{H_2}}{r_x}=\sqrt{\frac{M_x}{2}}\Rightarrow \frac{6}{1}=\sqrt{\frac{M_x}{2}}$

$M_x=36\times 2=72$