180ml of a hydrocarbon diffuses through a porous membrane in 15 minutes while 120ml of SOunder similar conditions diffuses in 20 minutes. What is the molecular mass of hydrocarbon? and how

Dear student,

Please find below the solution to the asked query.

According to Graham's law of diffusion:



r = rate of diffusion
M = Molecular mass

r = Volume effusedtime=Vt


r1r2 = M2M1V1/t1V2/t2 = M2M1180/15120/20=64M1 (Molecular mass of SO2 = 64 g/mol)180×20120×15 = 8M1M1 = 8×120×15180×20M1 = 4On squaring both sidesM1 = 16

So, molecular mass of the hydrocarbon = 16 g/mol

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