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

Question

7483 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2014-06-25T17:15:01

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

In your problem,

#n_"glycerol"# = 92 g glycerol × #(1"mol glycerol")/(92.09"g glycerol")# = 0.9990 mol glycerol (2 significant figures + 2 guard digits)

#n_"water"# = 90 g water × #(1"mol water")/(18.02"g water")# = 4.994 mol water

#n_"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.