Question

Given the amount of solute in grams and the volume of the solution in milliliters, how would you go about calculating the molarity of the solution? A) Divide the grams of solute by the volume in milliliters. B)Convert the grams of solute into moles and convert the volume from milliliters. Then divide the moles of solute by the volume in liters. C) Convert the grams of solute into moles. Then divide the moles of solute by the volume in milliliters. D) Convert the volume in milliliters to liters. Then divide the grams of solute by the volume in liters.

Answer 1

Molarity is defined as the number of moles of solute in 1 L of the solution.
Since the mass of the solute has been given we have to obtain the number of moles of solute
Number of moles = mass / molar mass
So we need to convert the mass to number of moles by dividing the mass by its molar mass.
The volume of the solution needs to be given in L but it has been measured in ml. Therefore volume in mL should be converted to L.
The molarity is found by dividing the number of moles by volume of solution in L
Answer is C)