Question

The gas which diffuses twice as quickly as So2

Answer 1

Rate of diffusion is inversely proportional to the square root of the molecular weight. Sulfur dioxide has a molecular weight of 64 and hence the square root is 8.

Since its inversely proportional, to be able to diffuse twice as fast, the square root of the molecular weight should be 4, and hence the molecular weight would be 16. So the answer is methane (CH4).