Problem 66
Which of the following ionic compounds will be more soluble in acid solution than in water: (a) \(\mathrm{BaSO}_{4}\), (b) \(\mathrm{PbCl}_{2}\) (c) \(\mathrm{Fe}(\mathrm{OH})\) (d) \(\mathrm{CaCO}_{3} ?\)
Problem 67
Which of the following will be more soluble in acid solution than in pure water: (a) CuI, (b) \(\mathrm{Ag}_{2} \mathrm{SO}_{4}\), (c) \(\mathrm{Zn}(\mathrm{OH})_{2}\) (d) \(\mathrm{BaC}_{2} \mathrm{O}_{4}\) (e) \(\mathrm{Ca}_{3}\left(\mathrm{PO}_{4}\right)_{2} ?\)
Problem 70
The solubility product of \(\mathrm{Mg}(\mathrm{OH})_{2}\) is \(1.2 \times 10^{-11} .\) What minimum \(\mathrm{OH}^{-}\) concentration must be attained (e.g., by adding \(\mathrm{NaOH}\) ) to decrease the Mg concentration in a solution of \(\mathrm{Mg}\left(\mathrm{NO}_{3}\right)\), to less than \(1.0 \times 10^{-10} \mathrm{M} ?\)
Problem 73
Calculate the concentrations of \(\mathrm{Cd}^{2+}, \mathrm{Cd}(\mathrm{CN})_{4}^{2-},\) and \(\mathrm{CN}^{-}\) at equilibrium when \(0.50 \mathrm{~g}\) of \(\mathrm{Cd}\left(\mathrm{NO}_{3}\right)_{2}\) dissolves in \(5.0 \times 10^{2} \mathrm{~mL}\) of \(0.50 \mathrm{M} \mathrm{NaCN}\)
Problem 74
If \(\mathrm{NaOH}\) is added to \(0.010 \mathrm{M} \mathrm{Al}^{3+},\) which will be the predominant species at equilibrium: \(\mathrm{Al}(\mathrm{OH})_{3}\) or \(\mathrm{Al}(\mathrm{OH})_{4}^{-} ?\) The \(\mathrm{pH}\) of the solution is \(14.00 .\left[K_{\mathrm{f}}\right.\) for \(\mathrm{Al}(\mathrm{OH})_{4}^{-}=2.0 \times 10^{33}\)
Problem 76
Both \(\mathrm{Ag}^{+}\) and \(\mathrm{Zn}^{2+}\) form complex ions with \(\mathrm{NH}_{3}\). Write balanced equations for the reactions. However, \(\mathrm{Zn}(\mathrm{OH})_{2}\) is soluble in \(6 \mathrm{M} \mathrm{NaOH},\) and \(\mathrm{AgOH}\) is not. Explain.
Problem 78
Outline the general procedure of qualitative analysis.
Problem 82
In a group 1 analysis, a student obtained a precipitate containing both \(\mathrm{AgCl}\) and \(\mathrm{PbCl}_{2}\). Suggest one reagent that would enable the student to separate \(\mathrm{AgCl}(s)\) from \(\mathrm{PbCl}_{2}(s)\)
Problem 83
In a group 1 analysis, a student adds \(\mathrm{HCl}\) acid to the unknown solution to make \(\left[\mathrm{Cl}^{-}\right]=0.15 M .\) Some \(\mathrm{PbCl}_{2}\) precipitates. Calculate the concentration of \(\mathrm{Pb}^{2+}\) remaining in solution.
Problem 84
Both \(\mathrm{KCl}\) and \(\mathrm{NH}_{4} \mathrm{Cl}\) are white solids. Suggest one reagent that would enable you to distinguish between these two compounds.
