Question

Which of the following statements is true? The square root of the molecular weight of a gas is equal to its rate of diffusion. The rate of diffusion of a gas in inversely proportional to the square root of its molecular weight. The rate of diffusion of a gas is directly proportional to the square root of its molecular weight. The square root of the molecular weight of a gas is not related to its rate of diffusion.

Answer 1

the diffusion coefficient of the gas is proportional to the average rate of thermal motion of the molecules.

the average velocity is inversely proportional to the square root of the molar mass

so
The gas diffusion rate is inversely proportional to the square root of its molecular weight.

Answer 2

The answer is: The rate of diffusion of a gas in inversely proportional to the square root of its molecular weight.