A vessel with small opening contained equal volumes of oxygen and an unknown gas. Oxygen effused through the opening 1.8 times faster than the unknown gas. If the atomic mass of oxygen is 16, calculate the molecular mass of the unknown gas.

A vessel with small opening contained equal volumes of oxygen and an u

1.	A vessel with small opening contained equal volumes of oxygen and an unknown gas. Oxygen effused through the opening 1.8 times faster than the unknown gas. If the atomic mass of oxygen is 16, calculate the molecular mass of the unknown gas.
Answer» Solution :Graham.s LAW of diffusion is also applicable to the phenomenon of EFFUSION. According to this law, `r_1/r_2 = sqrt(M_2/M_1)` SINCE, oxygen EFFUSES 1.8 times FASTER than the unknown gas, we have `r_1/r_2 = 1.8` Suppose the molecular mass of the unknown gas is `M_2`. Hence, `1.8 = sqrt(M_2/32)( :. "Molecular mass of " O_2 = 32)` or`M_2 = 103.68`