# What are the mole fractions of the components of the solution formed when 92 g glycerol is mixed with 90 g water?

Jun 25, 2014

You can read how to calculate mole fractions in:
How do you calculate mole fractions?

${n}_{\text{glycerol}}$ = 92 g glycerol × $\left(1 \text{mol glycerol")/(92.09"g glycerol}\right)$ = 0.9990 mol glycerol (2 significant figures + 2 guard digits)

${n}_{\text{water}}$ = 90 g water × $\left(1 \text{mol water")/(18.02"g water}\right)$ = 4.994 mol water

${n}_{\text{total" = n_"glycerol" + n_"water}}$ = 0.9990 mol + 4.994 mol = 5.993 mol

The mole fraction Χ of glycerol is

Χ_"glycerol" = n_"glycerol"/n_"total" = (0.9990"mol")/(5.993"mol") = 0.17

The mole fraction of water is

Χ_"water" = n_"water"/n_"total" = (4.994"mol")/(5.993"mol") = 0.83

Note: The required answers can have only 2 significant figures, because that is all you gave for the masses of glycerol and water.

Hope this helps.