Test: Comprehension Based Questions: States of Matter - JEE MCQ

X and Y are two volatile liquids with molar weights of 10 g mol^–1 and 40 g mol^–1 respectively. Two cotton plugs, one soaked in X and the other soaked in Y, are simultaneously placed at the ends of a tube of length L = 24 cm, as shown in the figure.  The tube is filled with an inert gas at 1 atmosphere pressure and a temperature of 300 K. Vapours of X and Y react to form a product which is first
observed at a distance d cm from the plug soaked in X. Take X and Y to have equal molecular diameters and assume ideal behaviour for the inert gas and the two vapours.

Q. The value of d in cm (shown in the figure), as estimated from Graham’s law, is    (JEE Adv. 2014)

X and Y are two volatile liquids with molar weights of 10 g mol^–1 and 40 g mol^–1 respectively. Two cotton plugs, one soaked in X and the other soaked in Y, are simultaneously placed at the ends of a tube of length L = 24 cm, as shown in the figure.  The tube is filled with an inert gas at 1 atmosphere pressure and a temperature of 300 K. Vapours of X and Y react to form a product which is first
observed at a distance d cm from the plug soaked in X. Take X and Y to have equal molecular diameters and assume ideal behaviour for the inert gas and the two vapours.

Q. The experimental value of d is found to be smaller than the estimate obtained using Graham’s law. This is due to (JEE Adv. 2014)