Question

See the figure

The valves of X and Y are opened simultaneously.

The white fumes of $N{H}_{4}Cl$ will first form close to which of A, B and C?

• A. A
• B. B
• C. C
• D. A,B and C simultaneously

Answer 1

The correct option is C

C

The rates of diffusion are inversely proportional to the square root of molecular mass. Thus, lower the molecular mass of the molecule, higher the rate of effusion/diffusion. The molecular mass of ammonia is lower than that of HCl, almost twice that of HCl. So, it is the rate of diffusion of ammonia will be almost twice that of HCl. This would mean that ammonia would travel a longer distance in the same time as compared to HCl. So, the closest option would be point C.