You are given 450.0 g of a 0.7500 molal solution of acetone dissolved in water. how many grams of acetone are in this amount of solution?

Molality is the number of moles dissolved in one kilogram of solvent.

m = n/kg of solvent

n = mass of solute / molar mass of solute

Acetone's chemical formula is C3H6O. Therefore, its molar mass = 12*3 + 6*1 + 1*16 = 58g = 0.058kg

n = mass of solute / 0.058

We have the molality = 0.7500 and the mass of solution = mass of solvent + mass of solute = 450 g = 0.45 kg

Therfore, mass of solvet = 0.45 - mass of solute

0.75 = n / 0.45 - mass of solute

0.75 = (mass of solute / 0.058) / (0.45 - mass of solute)

Let mass of solute = x

0.75 = (x/0.058) / (0.45 - x)

0.3375 - 0.75x = x/0.058

x = 0.019575 - 0.0435x

1.0435x = 0.019575

x = 0.01875 kg

mass of acetone = 0.01875 kg = 18.75 grams