How should the rate of diffusion of helium compare to that of sulfur dioxide?
Graham's law of effusion holds that the relative rate of effusion/diffusion of 2 gases is inversely proportional to the square root of the molecular masses of the two diffusing gases.....
And so helium should diffuse/effuse FOUR TIMES as FAST as sulfur dioxide. What is special about the molecular mass of each gas; i.e. why were these 2 gases quoted for the problem?