1. Lecture 92/09/06

2. A chemistry student mixes 20.0 mL of 4.5 x 10 -3 M AgNO 3 with 10.0 mL of 7.5 x 10 -2 M of NaBrO 3. Will a precipitate of AgBrO 3 form? K sp (AgBrO 3 ) = 6.7 x 10 -5

3. K sp (AgCl) = 1.8 x 10 -10. If you have solution that is 1.0 x 10 -5 M Ag +, what is the minimum Cl - concentration for a precipitate to form?

4. Separations Using the solubility rules, how could you separate the following ion pairs? 1. Na + and Ba 2+ 2. Pb 2+ and Ca 2+

5. Solubility Rules Soluble CompoundsExceptions NO 3 - None C 2 H 3 O 2 - (acetate)None Cl -, Br -, I - Compounds with Ag +, Hg 2 2+, Pb 2+ SO 4 2- Compounds with Sr 2+, Ba 2+, Hg 2 2+, Pb 2+ Group 1A and NH 4 + None Insoluble CompoundsExceptions S 2- Group 1A and NH 4 + [Ca 2+, Sr 2+, Ba 2+ ] CO 3 2-,PO 4 3-, C 2 O 4 2-, CrO 4 2- Group 1A and NH 4 + OH - Group 1A and NH 4 + [Ca 2+, Sr 2+, Ba 2+ ]

6. Cu 2+ and Ag + are found together in aqueous solution. Using the table of solubility product constants devise a way to separate these ions by adding one reagent to precipitate one of them as an insoluble salt and leave the other in solution. Cu +, Cu 2+ CuBr 6.3 x 10 -9 CuI 1.3 x 10 -12 Cu(OH) 2 2.2 x 10 -20 CuSCN 6.3 x 10 -9 Ag + AgBr 5.4 x 10 -13 AgBrO 3 5.4 x 10 -5 AgCH 3 CO 2 1.9 x 10 -3 AgCN 6.0 x 10 -17 Ag 2 CO 3 8.5 x 10 -12 Ag 2 C 2 O 4 5.4 x 10 -12 AgCl 1.8 x 10 -10 Ag 2 CrO 4 1.1 x 10 -12 AgI 8.5 x 10 -17 AgSCN 1.0 x 10 -12 Ag 2 SO 4 1.2 x 10 -5

7. If HCl is added slowly to a solution that is 0.10 M Pb 2+ and 0.01 M Ag +. K sp (AgCl) = 1.6 x 10 -10 K sp (PbCl 2 ) = 2.4 x 10 -4 Which precipitates first AgCl or PbCl 2 ?