Question

Three different gases X,Y and Z of molecular masses 2, 16 and 64 were enclosed in a vessel at constant temperature till equilibrium is reached. Which of the following statement is CORRECT?

• A. Gas Z will be at top of the vessel.
• B. Gas Y will be at the top of the vessel.
• C. Gas Z will be at the bottom and X will be at the top.
• D. Gases will form homogeneous mixture.

Answer 1

Answer: (D)

Gases will form homogeneous mixture.

Gases of same or different molecular weight always mix homogeneously.

For instance, air is an example of homogeneous mixture. we know in air, contains 78% nitrogen, 21% oxygen and some amount of carbon and other gases. here you can see molecular weight of nitrogen , carbon dioxide and oxygen are different in spite of this, these are mix homogeneously.

same here, X , Y and Z are different gases and out in closed vessel at constant temperature then, after equilibrium, gases are homogeneously present in the vessel.