Q106 / 200 · MHT CET - Medical 2026 (24 April Shift 1) · Chemistry
Which of the following relations is correct regarding rate of diffusion of a gas?
- Adirectly proportional to its density
- Bdirectly proportional to its molecular mass
- Cdirectly proportional to the square of its molecular mass
- Correct answerDinversely proportional to the square root of its molecular mass
Solution
According to Graham's law of diffusion, under identical conditions of temperature and pressure, the rate of diffusion of a gas is inversely proportional to the square root of its density or molecular mass.
$r \propto \dfrac{1}{\sqrt{M}}$
where $r$ is the rate of diffusion and $M$ is the molecular mass of the gas.
Therefore, the rate of diffusion is inversely proportional to the square root of its molecular mass.
Answer: inversely proportional to the square root of its molecular mass
$r \propto \dfrac{1}{\sqrt{M}}$
where $r$ is the rate of diffusion and $M$ is the molecular mass of the gas.
Therefore, the rate of diffusion is inversely proportional to the square root of its molecular mass.
Answer: inversely proportional to the square root of its molecular mass
Hence, the correct answer is option: 'D'.