If a gas diffuses at the rate of one-half as fast as O_(2), find the molecular mass of the gas.

If a gas diffuses at the rate of one-half as fast as O_(2), find the m

1.	If a gas diffuses at the rate of one-half as fast as O_(2), find the molecular mass of the gas.
Answer» Solution :Applying Graham.s law of diffusion . `(r_(1))/(r_(2)) = SQRT((M_(2))/(M_(1))) , (1/2)/(1) = sqrt((32)/(M_(1)))` Squaring both sides of the equation `((1)/(2))^(2) = (32)/(M_(1)) (or) (1)/(4) = (32)/(M_1)` `M_1 = 128` Thus the molecular mass of the unknown gas is 128.