Calculate the mole fraction of ethylene glycol in a solution containing 20% of ethylene glycol by mass.

20% of ethylene glycol is present in 100% soln. that means, 20 gm of ethylene glycol is present in 100 gm of glycol soln. Therfore, the moles of ethylene glycol = 20/62
= 0.322 mol.
moles of water
= (100 – 20)/18 = 80/18
= 4.44 moles.
Mole fraction for ethylene glycol
= 0.322/(0.322 + 4.44) =>0.06761