Diffusion is that property by virtue of which a perfume bottle when opened up in a room, makes the whole room fragrant with its smell. If a perfume ‘X’ diffuses twice as fast as another perfume ‘Y’; what is the molecular weight of ‘Y’, if the vapor density of gas ‘X’ is 2? Molecular weight of gas ‘X’ is to be assumed to be 2 ?

Question

Accepted Answer

16. Rate of diffusion is inversely proportional to the square root of molecular weight. Since X diffuses twice as fast as Y, its molecular weight is one-fourth that of Y. With vapor density of X being 2 (molecular weight 4), Y's molecular weight is 16.