Calculate the mole fraction of ethylene glycol (C2H6O2) in a solution containing 20% of C2H6O2 by mass.
Mass of ethylene glycol in 100g of solution= 20g
Mass of water in 1oo g solution= 80g.
Number of moles of ethylene glycole= 20/69 =0.2
Number of moles of water =80/18 =4.44
Therefore,
Mole fraction of ethylene glycol = 0.2/(4.44+0.2) = 0.04