In water (volume 0.04 l), propanol was dissolved, extracted with chloropropane (weight 9.8 g)

In water (volume 0.04 l), propanol was dissolved, extracted with chloropropane (weight 9.8 g), containing 20% of impurities. Determine the mass fraction of propanol in the solution.

To begin with, we write down the first equation for obtaining propanol from chloropropane:
C3H7Cl + NaOH = C3H7OH + NaCl
Now we need to find exactly how much pure chloropropane we have:
To do this, multiply 9.8 by 80%:
m = 9.8 * 0.8 = 7.84 grams.
Let’s write down the proportion:
7.84 – x
78.5 – 60
Where 6 x = 7.84 * 60 / 78.4 = 6 grams
To calculate the mass fraction, we find the mass of the solvent: the density of water is 1 g / ml
We have 0.04 l or 40 ml of water
Find the mass: m = 40 ml * 1 g / ml = 40 grams
Then the mass fraction of propanol is equal to:
w = 6 / (6 + 40) = 6/46 = 13%