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A solution is made by mixing 36 g of water with 46 g of glycerine, C3H5(OH)3. Find the mole fraction of glycerine. (Molar masses: water = 18, glycerine = 92)

1. 0.20
2. 0.46
3. 0.36
4. 0.40

Correct answer: 0.20

Solution

With 2 mol water and 0.5 mol glycerine, x(glycerine) = 0.5/(2 + 0.5) = 0.5/2.5 = 0.20.

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