Copyright 2016 Dan Dill 1

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1 carbonate These solutions are mixed and a precipitate forms. After the precipitation, the solution 1. will be positively charged 2. will be electrically neutral 3. will be negatively charged 4. More information needed Lecture 19 CH101 A1 (MWF 9 am) Friday, October 21, 2016 Complete: Concentrations after precipitation Self ionization of water Acid base reactions: Competition for H ; Next lecture: Complete acid base reactions: Competition for H ; balancing oxidation reduction equations; complexation as Lewis acidbase reaction 1 carbonate These solutions are mixed and a precipitate forms. The limiting reagent is. 1. BaI 2 s 2. NH 4 2 CO 3 s 3. NH 4 aq 4. Ba aq 5. CO 6. I aq BaI 2 s Ba aq 2 I aq NH 4 aq Ba aq CO 3 aq I aq M L mol 0.40 M L mol 0.20 M L mol M L mol 6 7 1

2 BaI 2 s Ba aq 2 I aq Ba aq CO BaCO 3 s These solutions are mixed and a precipitate forms. Write the net ionic equation for this process. What are the spectator ions for this process? What is the limiting reactant? How many moles of the solid precipitate are formed? After precipitation, what are the molarities M of each ion in solution? 8 9 BaI 2 s Ba aq 2 I aq Ba aq CO BaCO 3 s BaI 2 s Ba aq 2 I aq Ba aq CO BaCO 3 s Ba aq CO BaCO 3 s start mol mol 0 change end 10 Ba aq CO BaCO 3 s start mol mol 0 change mol mol mol end mol mol 11 2

3 These solutions are mixed and a precipitate forms. Write the net ionic equation for this process. What are the spectator ions for this process? What is the limiting reactant? How many moles of the solid precipitate are formed? After precipitation, what are the molarities M of each ion in solution? Is the final solution electrically neutral? carbonate These solutions are mixed and a precipitate forms. After the precipitation, the solution 1. will be positively charged 2. will be electrically neutral 3. will be negatively charged 4. More information needed Ionization of molecular non ionic solutes Cl:H aq :OH 2 l H:OH aq Cl: aq Nearly complete reaction ~ 100 % theoretical yield 14 Strong electrolyte 15 3

4 Note: Unlike NaCl(aq), HCl(aq) does exist CH 3 C O O:H aq :OH 2 l H:OH aq CH 3 C O O: aq Only a little reaction 100 % theoretical yield 16 Weak electrolyte 17 CH 3 CH 2 O:H aq :OH 2 l H:OH aq CH 3 CH 2 O: aq Almost no reaction 100 % theoretical yield HO:H aq :OH 2 l H:OH aq HO: aq Almost no reaction 100 % theoretical yield

5 HO:H aq :OH 2 l H:OH aq HO: aq ~10 7 mol/l HO:H aq :OH 2 l H:OH aq HO: aq ~10 7 mol/l. In pure water, how many water molecules are there for every OH ion? TP In pure water, how many water molecules are there for every OH ion? , ,000, ,000, More than 10,000,000 HO:H aq :OH 2 l H:OH aq HO: aq ~10 7 mol/l. H:OH aq, usually written H 3 O aq, is typically hydrogen bonded to several other water molecules, with the partners continually exchanging with other water molecules