1. Chapter 20 Concentration

2. Molarity (M) Moles of solute per liter of solution. Molarity = moles of solute liters of solution

3. What is the molarity of a solution prepared by dissolving 21.0 g of CaCl 2 in 500.0 mL of solution?

4. 0.378M CaCl 2

5. What is the molarity of a solution prepared by dissolving 48.4 g of CaCl 2 in 100.0 mL of solution?

6. 4.36M CaCl 2

7. molality (m) Moles of solute per kilogram of solvent. molality = moles of solute kg of solvent

8. What is the molality of a solution prepared by dissolving 92.3 g of KF in 100.0g of water?

9. 15.9m KF

10. What is the molality of a solution prepared by dissolving 20.0g of NH 4 Cl in 400.0g of water?

11. 0.935m NH 4 Cl

12. Mole Fraction (X) moles of component per total moles of solution. mole fraction = moles of component total moles in solution Note: The mole fractions of the solute and solvent add up to “1”

13. What is the mole fraction of C 4 H 10 O in a solution containing 75.6g of C 10 H 8 and 600.0g of C 4 H 10 O?

14. X C 4 H 10 O = 0.932

15. What is the mole fraction of C 2 H 6 O in a solution containing 67.4g of C 9 H 7 N and 200.0g of C 2 H 6 O?

16. X C 2 H 6 O = 0.893

17. Percent Solution by mass Represents the number of grams of solute per 100 grams of solution. % solution = mass of solute mass of solution X 100

18. A solution contains 130g of HCl in 750g of water. What is the percent by mass of this HCl solution?

19. 14.8% HCl

20. What is the mass percent of a solution containing 67.4g of C 9 H 7 N in 200.0g of C 2 H 6 O?

21. 25.2% C 9 H 7 N

22. Homework Worksheet: Concentration