What is the molarity of a solution that is prepared by adding 57.1 g of toluene (c 7 h 8 ) (density = 0.867 g/ml) to a 250 ml volumetric flask, and then filling to the mark with benzene (c 6 h 6 ) (density = 0.876 g/ml)?

2.48 mol/L.

Explanation:

M = (mass / molar mass) solute x (1000 / V of solution)

The solute is toluene and the solvent is benzene.

mass of toluene (solute) = 57.1 g,

molar mass of toluene (solute) = 92.14 g/mol.

volume of the solution = 250 ml.

∴ M =  (mass / molar mass) solute x (1000 / V of solution) = [(57.1 g / 92.14 g/mol) x (1000 / 250 ml)] = 2.48 mol/L.