Helium effuses through a small opening at a rate of 1×10^-⁹ mol s^-¹. An unknown gas at the same temperature and pressure is found to effuse through the same opening at a rate of 3.78×10^-¹⁰ mol s^-¹. What is the molecular mass of the unknown gas?

Question

Quizplus · Accepted Answer

Using Graham's law of effusion, the rate of effusion is inversely proportional to the square root of the molar mass. Solving for the unknown gas's molar mass gives approximately 28 g/mol.

Helium Effuses Through a Small Opening at a Rate of 1×10-9

Helium Effuses Through a Small Opening at a Rate of 1×10^-⁹