Acetone, C3H6O, is the main ingredient of nail polish remover. A solution is made up by adding 35.0mL of acetone(d=0.790g/mL) to 50.0mL of ethyl alcohol,C2H6O(d=0.798 g/mL). Assume that the volumes are additive. From this information calculate the molarity of acetone in the solution.

Question

Acetone, C3H6O, is the main ingredient of nail polish remover.  A solution is made up by adding 35.0mL of acetone(d=0.790g/mL) to 50.0mL of ethyl alcohol,C2H6O(d=0.798 g/mL).  Assume that the volumes are additive.  From this information calculate the molarity of acetone in the solution.

My answer was 2.3g, but it was wrong.

Ian · Answer

Ok, given the volume and density, you can determine the grams of each compound present.

That leaves you with needing to find the moles of acetone in the solution of 85mL, or 0.085L.

Now, what quantity can you calculate that would relate grams and moles? Think periodic table.

Once you know the number of moles you can calculate the molarity.

Molarity= mole solute / L of solution