An aqueous solution of ethanol, CH3CH2OH, has a concentration of 5.82 mol/L and has a density of 0.957 g/mL. What are the mass percent and mole fraction of CH3CH2OH in this solution

1. Mass percent of ethanol = 28.02 %.

2. Mole fraction of ethanol = 0.13.

Explanation:

1. To find the mass percent we need to use the following equation:

Where:

is the mass of ethanol

is the mass of the solution

We need to calculate the mass of ethanol and the mass of the solution:

Where:

d: is the density of the solution = 0.957 g/mL

V: is the volume = 1 L

Now, from the concentration we can find the mass of ethanol:

Where:

: is the molar mass of ethanol = 46.07 g/mol

: is the number of moles of ethanol = m/M

Finally, the mass percent of ethanol is:

2. The mole fraction of ethanol is given by:

The number of moles of ethanol is:

And the moles of the solution is:    

Where w is for water

Hence, the mole fraction of ethanol is:

I hope it helps you!                                                          

fe 55.85 g/mol and h2o 18.02 g/mol.