Solution Concentrations
1. A solution is prepared by dissolving 50.55 g of KNO3 in 1500. g of water and the final volume of the solution is
1510 mL. Assume that the density of water is 1.00 g/mL and the molar masses of KNO3 and water are 101.1 g/mol
and 18.02 g/mol respectively. Use the information to calculate the following:
Molarity
Molality
Percent by mass
Mole fraction
Density
Parts per million
Chapter 12 - Solution Concentrations
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CHEM 2061 SP16 - BH
2. What is the molality of a 2.50 M aqueous solution of KCl? (density = 1.15 g/mL and molar mass of KCl = 74.55 g/mol)
3. An aqueous solution is 32.0% HBr by mass and has a density of 1.10 g/mL (HBr has a molar mass of 80.91 g/mol).
What is the molarity and molality of the solution?
4. A 3.50 L aqueous solution of sucrose (C12H22O11, molar mass = 342.30 g/mol) has a molality of 1.10 m and a density
of 1.20 g/cm3. What is the molarity of the solution?
Chapter 12 - Solution Concentrations
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CHEM 2061 SP16 - BH