Chapter 23

In your own words, define the following terms: (a) domain; (b) flotation; (c) leaching; (d) amalgam.

Briefly describe each of the following ideas, phenomena, or methods: (a) lanthanide contraction; (b) zone refining; (c) basic oxygen process; (d) slag formation.

Explain the important distinctions between each pair of terms: (a) ferromagnetism and paramagnetism; (b) roasting and reduction; (c) hydrometallurgy and pyrometallurgy; (d) chromate and dichromate.

Describe the chemical composition of the material called (a) pig iron; (b) ferromanganese alloy; (c) chromite ore; (d) brass; (e) aqua regia; (f) blister copper; (g) stainless steel.

Three properties expected for transition elements are (a) low melting points; (b) high ionization energies; (c) colored ions in solution; (d) positive standard electrode (reduction) potentials; (e) diamagnetism; (f) complex ion formation; (g) catalytic activity.

The only diamagnetic ion of the following group is (a) \(\mathrm{Cr}^{2+} ;\) (b) \(\mathrm{Zn}^{2+} ;\) (c) \(\mathrm{Fe}^{3+} ;\) (d) \(\mathrm{Ag}^{2+} ;\) (e) \(\mathrm{Ti}^{3+}\).

All of the following elements have an ion displaying the +6 oxidation state except (a) Mo; (b) Cr; (c) Mn; (d) \(\mathrm{V} ;\) (e) S.

The best oxidizing agent of the following group of ions is (a) \(\mathrm{Ag}^{+}(\mathrm{aq}) ;\) (b) \(\mathrm{Cl}^{-}(\mathrm{aq}) ;\) (c) \(\mathrm{H}^{+}(\mathrm{aq})\) (d) \(\mathrm{Na}^{+}(\mathrm{aq}) ;\) (e) \(\mathrm{OH}^{-}(\mathrm{aq})\)

To separate \(\mathrm{Fe}^{3+}\) and \(\mathrm{Ni}^{2+}\) from an aqueous solution containing both ions, with one cation forming a precipitate and the other remaining in solution, add to the solution (a) \(\mathrm{NaOH}(\mathrm{aq}) ;\) (b) \(\mathrm{H}_{2} \mathrm{S}(\mathrm{g})\) (c) \(\mathrm{HCl}(\mathrm{aq}) ;(\mathrm{d}) \mathrm{NH}_{3}(\mathrm{aq})\)

Of the following, the two solids that will liberate \(\mathrm{Cl}_{2}(\mathrm{g})\) when heated with \(\mathrm{HCl}(\mathrm{aq})\) are \((\mathrm{a}) \mathrm{NaCl}(\mathrm{s})\) (b) \(\mathrm{ZnCl}_{2}(\mathrm{s}) ;(\mathrm{c}) \mathrm{MnO}_{2}(\mathrm{s}) ;(\mathrm{d}) \mathrm{CuO}(\mathrm{s}) ;(\mathrm{e}) \mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}(\mathrm{s})\) (f) \(\mathrm{NaOH}(\mathrm{s})\)

Balance the following oxidation-reduction equations. $$\text { (a) } \mathrm{Fe}_{2} \mathrm{S}_{3}(\mathrm{s})+\mathrm{H}_{2} \mathrm{O}+\mathrm{O}_{2}(\mathrm{g}) \longrightarrow \mathrm{Fe}(\mathrm{OH})_{3}(\mathrm{s})+\mathrm{S}(\mathrm{s})$$ $$\begin{aligned} &\text { (b) } \mathrm{Mn}^{2+}(\mathrm{aq})+\mathrm{S}_{2} \mathrm{O}_{8}^{2-}(\mathrm{aq})+\mathrm{H}_{2} \mathrm{O} \longrightarrow\\\ &&\mathrm{MnO}_{4}^{-}(\mathrm{aq})+\mathrm{SO}_{4}^{2-}(\mathrm{aq})+\mathrm{H}^{+}(\mathrm{aq}) \end{aligned}$$ $$\begin{aligned} &\text { (c) } \mathrm{Ag}(\mathrm{s})+\mathrm{CN}^{-}(\mathrm{aq})+\mathrm{O}_{2}(\mathrm{g})+\mathrm{H}_{2} \mathrm{O} \longrightarrow\\\ &&\left[\mathrm{Ag}(\mathrm{CN})_{2}\right]^{-}(\mathrm{aq})+\mathrm{OH}^{-}(\mathrm{aq}) \end{aligned}$$

Explain why \(\mathrm{Zn}, \mathrm{Cd},\) and \(\mathrm{Hg}\) resemble the group 2 metals in some of their properties.

Explain why gold dissolves in aqua regia but not in \(\mathrm{HNO}_{3}(\mathrm{aq})\).

Explain why \(1.0 \mathrm{M} \mathrm{Fe}\left(\mathrm{NO}_{3}\right)_{3}(\mathrm{aq})\) is acidic.