MOLARITY A measurement of the concentration of a

MOLARITY A measurement of the concentration of a solution Molarity (M) is equal to the moles of solute (n) per liter of solution M = n / V = mol / L 1. Calculate the moles necessary to make 50. 0 m. L of a 3. 0 M solution of hydrochloric acid. 2. Calculate the molarity of a solution prepared by mixing 23. 0 g of Na. Cl in 500. 0 m. L of water. 3. How many grams of sodium sulfate will be required to make 150. 0 m. L of a 0. 25 M solution?

MOLARITY & DILUTION M 1 V 1 = M 2 V 2 The act of diluting a solution is to simply add more water (or solvent) thus leaving the amount of solute unchanged.

Q. Calculate the concentration of a Na. Cl solution made by diluting 20. 0 m. L of 2. 55 M with 235. 0 m. L of water.

MOLARITY & Stoichiometry In the past chapters, you measured out a solid reactant and needed to predict the mass of the product. You learned to use the molar mass and mole ratio to achieve that goal. The same reasoning applies with solution chemistry but instead to using the molar mass you will use the molarity to convert to moles. Stoichiometry Flow chart

Solution Stoichiometry

MOLARITY & Stoichiometry 1. How much calcium carbonate will be precipitated by adding 40. 0 m. L calcium chloride to 35. 0 m. L of 2. 55 M potassium carbonate? 2. What is the concentration of 50. 0 m. L of hydrochloric acid needed to completely react with 9. 55 g of magnesium metal?

PRACTICE PROBLEMS #37 a 2. 4 M _____1. What is the concentration of 250. 0 m. L of 0. 60 moles of HCl? 3. 00 L _____ 2. What volume of 0. 7690 M Li. OH will contain 55. 3 g of Li. OH? 1. 80 L 3. How many liters of water must be added to _____ 100. 0 m. L of 4. 50 M HBr to make a solution that is 0. 250 M HCl? 39. 6 g 4. How many grams of barium sulfate that will _____ precipitate when 500. 0 m. L of 0. 340 M Ba. Cl 2 and 300. 0 m. L of 1. 70 M Na 2 SO 4 are mixed? 5. How would you prepare 850. 0 m. L of a 0. 020 M ferric chloride solution if you start with crystals of Fe. Cl 3. 6 H 2 O? Weigh out 4. 59 g of the hydrated salt to a graduated cylinder with 800. 0 m. L then add enough DI water to make 850 m. L exactly.

PRACTICE PROBLEM #37 b 1. What is the concentration of 35. 0 m. L of 0. 0556 moles of KCl? 1. 59 M 2. How many grams of KCl is needed to prepare 50. 0 m. L of a 0. 10 M solution? 0. 38 g 3. How many milliliters of water must be added to 30. 0 m. L of 9. 0 M KCl to make a solution that is 0. 50 M KCl? 510 m. L 4. How many grams of calcium carbonate will precipitate when 500. 0 m. L of 0. 340 M Ca. Cl 2 and 300. 0 m. L of 1. 70 M Na 2 CO 3 are mixed? 17. 0 g 5. What is the concentration of the product solution (assuming the volumes are additive) when 500. 0 m. L of 0. 340 M Ca. Cl 2 and 300. 0 m. L of 1. 70 M Na 2 CO 3 are mixed? 0. 425 M

GROUP STUDY PROBLEM #37 a ______1. How many grams of K 3 PO 4 is needed to prepare 500. 0 m. L of a 0. 00567 M solution? ______2. What volume of 0. 7690 M Li. OH will contain 55. 3 g of Li. OH? ______3. How many milliliters of water must be added to 600. 0 m. L of 3. 40 M HCl to make a solution that is 0. 500 M HCl? ______ 4. What is the concentration of the product solution (assuming the volumes are additive) when 24. 9 m. L of 0. 70 M Ba. Cl 2 and 45. 0 m. L of 0. 15 M Na 3 PO 4 are mixed?

GROUP STUDY PROBLEM #37 b ______1. What is the concentration of 250. 0 m. L of 0. 60 moles of Na. OH? ______2. What mass of Mg. Cl 2 will be required to prepare 500 m. L of 0. 150 M solution? ______3. How many milliliters of water must be added to 50. 0 m. L of 1. 97 M Na. OH to make a solution that is 0. 025 M Na. OH? ______ 4. How many grams of barium sulfate that will precipitate when 500. 0 m. L of 0. 340 M Ba. Cl 2 and 300. 0 m. L of 1. 70 M Na 2 SO 4 are mixed? ______ 5. What is the concentration of the product solution (assuming the volumes are additive) when 500. 0 m. L of 0. 340 M Ba. Cl 2 and 300. 0 m. L of 1. 70 M Na 2 SO 4 are mixed?