Analytical Chem istry - DePauw University

Chapter 6 Equilibrium Chemistry273oxidizing agent to convert 0.002 mol of Fe 2+ to Fe 3+ ? Be sure to stateand justify any assumptions you make in solving the problem.24. Use either Excel or R to solve the following problems. For these problems,make no simplifying assumptions.a. the solubility of CaF 2 in deionized waterb. the solubility of AgCl in deionized water (see Problem 14 for therelevant equilibria)Most of the problems that follow require one ormore equilibrium constants or standard state potentials.For your convenience, here are hyperlinksto the appendices containing these constantsAppendix 10: Solubility ProductsAppendix 11: Acid Dissociation ConstantsAppendix 12: Metal-Ligand Formation ConstantsAppendix 13: Standard State Reduction Potentialsc. the pH of 0.10 M fumaric acid25. Beginning with the relevant equilibrium reactions, derive equation6.64 for the rigorous solution to the pH of 0.1 M HF.6OSolutions to Practice ExercisesPractice Exercise 6.1The overall reaction is equivalent toRxn4− 2×Rxn 1Subtracting a reaction is equivalent to adding the reverse reaction; thus,the overall equilibrium constant isKK4= = = ≈( )K150 .( 040 . )2 2Click here to return to the chapter.Practice Exercise 6.2The K b for hydrogen oxalate isKb,HC2Oand the K b for oxalate isK2b,C2O4Kw100 . × 10−= =4 K 560 . × 10a,H2CO2 4Kw100 . × 10−= =K 542 . × 10-a,HC2O431.25 31−14−2−14−5= 1.79× 10 −13= 1.85× 10 −10As we expect, the K b value for C 2 O 42–is larger than that for HC 2 O 4 – .Click here to return to the chapter.Practice Exercise 6.3We can write the reaction as the sum of three other reactions. The first ofthese reactions is the solubility of AgCl(s), which we characterize by itsK sp .