Question

A straight glass tube has two inlets X and Y at the two ends. The length of the tube is
200 cm. HCl gas through inlet X and NH3 gas through inlet Y are allowed to enter
the tube at the same time. White fumes first appear at a point P inside the tube. Find
the distance of P from X.​

Answer 1

Answer:

Explanation:

Let d cm be the distance of point P from end X of the tube.

So, distance from end Y = (200 - X) cm

Let rHCl be the rate of diffusion of HCl gas

 rNH3 be the rate of diffusion of NH3 gas

According to Graham's law:

rHClrNH3 = MNH3√MHCl√d200−d = 17√36.5√d200−d = 0.6824           d = 136.48 − 0.6824d  1.6824d = 136.48           d = 81.12 cmrHClrNH3 = MNH3MHCld200-d = 1736.5d200-d = 0.6824           d = 136.48 - 0.6824d  1.6824d = 136.48           d = 81.12 cm

Hence, the distance of point P from end X = 81.22 cm