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.

Ok is the mole of C3H6O 58.09mol, and if so, what do I do next?

The molar mass of acetone is correct.

Here is what you do.
Convert density acetone and density ethyl alcohol (together with volume) to grams,
density = mass x volume.
mass = density/volume. You are given the density of each and the volume of each. Determine mass of each.

Next, convert grams of each to moles.
moles = grams/molar mass.

Then molarity = moles/L and L = 50 mL + 35 mL = 85 mL = 0.085 L.

correction to the formula of density. density is equal to the ratio mass and volume, that is

d=m/v
m=d*v

steps to solve the molar refraction of acetone

To determine the molarity of acetone in the solution, you need to first calculate the moles of acetone present in the solution.

1. Start by calculating the mass of acetone present in the solution:
mass = volume x density

Using the given density of acetone (0.790 g/mL) and volume (35.0 mL):
mass of acetone = 35.0 mL x 0.790 g/mL
mass of acetone = 27.65 g

2. Next, convert the mass of acetone to moles using its molar mass (58.09 g/mol):
moles of acetone = mass / molar mass
moles of acetone = 27.65 g / 58.09 g/mol
moles of acetone = 0.476 mol

3. Now that you have the moles of acetone, you need to calculate the molarity. Molarity is defined as moles of solute divided by volume of solution in liters (mol/L):
molarity (M) = moles / volume in liters

The volume of the solution can be calculated by adding the volumes of acetone (35.0 mL) and ethyl alcohol (50.0 mL):
volume of solution = 35.0 mL + 50.0 mL
volume of solution = 85.0 mL

To convert mL to L, divide by 1000:
volume of solution = 85.0 mL / 1000
volume of solution = 0.085 L

Finally, calculate the molarity of acetone:
molarity of acetone = 0.476 mol / 0.085 L
molarity of acetone = 5.6 M

Therefore, the molarity of acetone in the solution is 5.6 M.

If you do everything I suggested, you will do more than necessary. I just worked the problem. You don't need the mass of ethyl alcohol nor the moles ethyl alcohol.