Question

Conversions

Example 2)

A 22% by mass solution of Acetic Acid ((C2H4O2)(MW=60.0520)) has a density of 1.029 g/mL. What is the molarity, molality and mole fraction of the Acetic Acid in the solution?

If you could show the steps as well that would be greatly appreciated! Thank you.

Answer 1

Assume that we have 100 g of solution (one can start with any amount of solution because the results obtained will be the same). Solution will contain 22 g of acetic acid and 78 g of water

Preliminary calculations:

mass of acetic acid = 22 gm

Moles of acetic acid = 22 / 60.052 = 0.333 Moles

Mass of water = 78 gm

Moels of water = 78 / 18 = 4.333 Moles

Molarity:

100 gm of solvent will be the volume = 100 /1.029 = 97.181

0.333 mol / 0.097181 L = 3.42 M

Molality:

0.333 mol / 0.1 kg = 3.33 m

Mole fraction of acetic acid:

0.333 mol / (0.333 mol + 4.333 mol) = 8.999

answered by: anonymous