Question

A straight glass tube as shown, has 2 inlets X & Y at the two ends of 200 cm long tube. HCl gas through inlet X and NH3 gas through inlet Y are allowed to enter in the tube at the same time and under the identical conditions. At a point P inside the tube both the gases meet first. The distance of point P from X is :

• A. 118.9 cm
• B. 81.1 cm
• C. 91.1 cm
• D. 108.9 cm

Answer 1

Answer: (B)

81.1 cm

Answer 2

$\frac{r_{HCl}}{r_{NH_{3}}} = \sqrt{\frac{17}{36.5}} \Rightarrow \frac{x}{200 - x} = \sqrt{\frac{17}{36.5}} \Rightarrow x = 81.13cm$