1. As you come in,  Collect the following: Solubility Graph Quiz, Concentration Quiz, paper, pencil, calculator, periodic table  Priorities: 1. Correct the Solubility Graph Quiz 2. Correct Concentration Quiz 3. Solve Dilution Worksheet (1/2 sheet) 4. Correct Colligative Properties Quiz 5. PowerPoint practice questions

3. 1. What is the molarity of a 125 mL solution in which 138.5 g of barium hydroxide are dissolved? 2. Determine the molality of a solution prepared by adding 243.6 g of aluminum nitrate to 750 g of water. 3. What volume of 0.8 M solution can be prepared if you have 47.8 g of Rb 2 SO 4 ? 4. What mass of ammonium phosphite is needed to prepare 625 ml of 0.5 M solution? 5. What mass of H 2 SO 4 is needed to prepare an aqueous 0.3 m H 2 SO 4 solution containing 1,500 g of water?

4. 1. What mass of ethylene glycol, HOCH 2 CH 2 OH must be added to 6000 g of water to produce an antifreeze solution that would protect a car radiator down to -21.2*C? K f for H 2 O is 1.86*C/m. 2. Which of the following aqueous solutions will give the highest boiling point? 1. 0.1 m KI b) 0.1 m CaF 2 c) 0.1 m AlPO 4 d) 0.1 m Mg 3 (PO 4 ) 2 e) all of these solutions will have the same boiling point 3. Determine the freezing point of a solution prepared by dissolving 0.1 mol of Al(NO 3 ) 3 in 500 g of water. The K f for water is 1.86*C/m. 4. The normal freezing point of carbon tetrachloride, CCl 4, is -22.3*C. A solution which freezes at -35.7*C is prepared using C 10 H 8 in 250 g of carbon tetrachloride whose K f is 29.8*C/m. Determine the mass of C 10 H 8 used. 5. The normal boiling point of ethanol is 78.4*C. If a solution is prepared by dissolving 14.8 g of AlBr 3 in 750 g of ethanol, what will the boiling point of the new solution be? The K b for ethanol is 1.22*C/m. 6. Which one of the following when dissolved in 100 g of water will give the solution of the lowest freezing point? K f for H 2 O is 1.86*C/m. a) 10 g methanol, CH 3 OH b) 10 g ethanol, C 2 H 5 OH c) 10 g glucose, C 6 H 12 O 6 d) 10 g glycerine, C 3 H 8 O 3 e) the freezing point will be the same in all cases 7. A solution of 15.1 grams of a non-electrolyte in 0.391 kilograms of H 2 O freezes at -2.02*C at standard pressure. What is the molar mass of the compound? The K f for H 2 O is 1.86*C/m.

5. Molarity, Molality and Dilution Practice 1. How many grams of sodium phosphate are needed to make 125mL of a 0.5M solution? 2. What is the molality of a solution made by dissolving 5.0g of toluene (C 7 H 8 ) in 225 g of benzene (C 6 H 6 )? 3. How much additional water is needed to change the molarity of 350mL of 4M H 2 SO 4 to a 2.5M solution?

6. Colligative Properties Practice  How many particles in solution are produced by each formula unit of potassium carbonate?  How many moles of particles would 3 mol sodium sulfate give in solution?  What is the boiling point of a solution that contains 2 mol of magnesium chloride in 100.0 g of water?  A solution of 4.69 g of a compound in 16.00 g of water boils at 100.83°C. What is the molar mass of the solute? Assume that the solute exists as molecules not ions.

7. Answers to the Practice  K 2 CO 3 contains 2 K + ions and 1 CO 3 -2 ion.  Use dimensional analysis. The solution gives 6 moles of Na + ions and 3 moles of SO 4 2- ions.  The boiling point of water containing 2 moles of MgCl 2 is 130.72°C.  The molar mass of the compound is 180.8 grams/mole.