Problem 44
The molar solubility of \(\mathrm{AgCl}\) in \(6.5 \times 10^{-3} \mathrm{M}\) \(\mathrm{AgNO}_{3}\) is \(2.5 \times 10^{-8} M .\) In deriving \(K_{\mathrm{sp}}\) from these data, which of these assumptions are reasonable? (a) \(K_{\mathrm{sp}}\) is the same as solubility. (b) \(K_{\mathrm{sp}}\) of \(\mathrm{AgCl}\) is the same in \(6.5 \times 10^{-3} \mathrm{M} \mathrm{AgNO}_{3}\) as in pure water. (c) Solubility of \(\mathrm{AgCl}\) is independent of the concentration of \(\mathrm{AgNO}_{3}\) (d) \(\left[\mathrm{Ag}^{+}\right]\) in solution does not change significantly on the addition of \(\mathrm{AgCl}\) to \(6.5 \times 10^{-3} \mathrm{M} \mathrm{AgNO}_{3}\). (e) \(\left[\mathrm{Ag}^{+}\right]\) in solution after the addition of \(\mathrm{AgCl}\) to \(6.5 \times 10^{-3} \mathrm{MAgNO}_{3}\) is the same as it would be in pure water.
Problem 45
How many grams of \(\mathrm{CaCO}_{3}\) will dissolve in \(3.0 \times\) \(10^{2} \mathrm{~mL}\) of \(0.050 \mathrm{M} \mathrm{Ca}\left(\mathrm{NO}_{3}\right)_{2} ?\)
Problem 46
The solubility product of \(\mathrm{PbBr}_{2}\) is \(8.9 \times 10^{-6} .\) Determine the molar solubility (a) in pure water, (b) in \(0.20 M\) KBr solution, (c) in \(0.20 \mathrm{M} \mathrm{Pb}\left(\mathrm{NO}_{3}\right)_{2}\) solution.
Problem 50
Give an example to illustrate the general effect of complex ion formation on solubility.
Problem 51
Write the formation constant expressions for these complex ions: (a) \(\mathrm{Zn}(\mathrm{OH})_{4}^{2-},\) (b) \(\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}^{3+}\) (c) \(\mathrm{HgI}_{4}^{2-}\).
Problem 52
Explain, with balanced ionic equations, why (a) \(\mathrm{CuI}_{2}\) dissolves in ammonia solution, (b) AgBr dissolves in NaCN solution, (c) \(\mathrm{Hg}_{2} \mathrm{Cl}_{2}\) dissolves in \(\mathrm{KCl}\) solution.
Problem 54
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 55
If \(\mathrm{NaOH}\) is added to \(0.010 \mathrm{MAl}^{3+}\), 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 57
Outline the general principle of qualitative analysis.
Problem 58
Give two examples of metal ions in each group (1 through 5) in the qualitative analysis scheme.
