Question

50 mL of $H_2$ gas diffuses through a small hole from a vessel in 20 min. Time taken by 40 mL of $O_2$ gas to diffuse under similar conditions will be :

• A. 12 min
• B. 64 min
• C. 8 min
• D. 32 min

Answer 1

The correct option is B

64 min

$r_{H_2}=\frac{50}{20}=2.5$

$r_{O_2}=\frac{40}{t}$

$\frac{r_{H_2}}{r_{O_2}}=\frac{2.5}{\frac{40}{t}}=\sqrt{\frac{M_{O_2}}{M_{H_2}}}=\sqrt{\frac{32}{2}}=4$

2.5 t = 160

t = 64 min.