The molar mass of an unknown gas was measured by an effusion experiment.It was found that it took 60 s for the gas to effuse,whereas nitrogen gas required 48 s.The molar mass of the gas is
A)25 g/mol.
B)35 g/mol.
C)18 g/mol.
D)31 g/mol.
E)44 g/mol.

Question

Quizplus · Accepted Answer

Using Graham's law of effusion, the ratio of effusion times is proportional to the square root of the inverse ratio of molar masses. Given that nitrogen (N2) has a molar mass of 28 g/mol, the calculation shows the unknown gas has a molar mass of approximately 44 g/mol.

The Molar Mass of an Unknown Gas Was Measured by an Effusion