A solution of ethanol (C2H5OH) in water is prepared by dissolving 57.0 mL of ethanol (density = 0.79 g/cm3) in enough water to make 240.0 mL of solution. What is the molarity of the ethanol in this solution?

Answer 1

mass = volume x density. Use this to calculate the mass of ethanol.
mols ethanol = grams/molar mass.
M = mols/L = mols ethanol/0.240 L = ??