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Addition of chloride ions to a suspension of PbCl 2 gives rise to soluble complex ions. In these reactions the additional chloride (or other ligands) break up the chloride bridges that comprise the polymeric framework of solid PbCl 2(s). PbCl 2(s) + Cl − → [PbCl 3] − (aq) PbCl 2(s) + 2 Cl − → [PbCl 4] 2− (aq) PbCl 2 reacts with ...
PbCl 2, PbBr 2 and PbI 2 are commonly used to produce donor centers. Other n-type doping agents such as Bi 2 Te 3 , TaTe 2 , MnTe 2 , will substitute for Pb and create uncharged vacant Pb-sites. These vacant sites are subsequently filled by atoms from the lead excess and the valence electrons of these vacant atoms will diffuse through crystal.
It is then converted to the ammonium salt (NH 4) 2 PbCl 6 by adding ammonium chloride (NH 4 Cl). Finally, the solution is treated with concentrated sulfuric acid H 2 SO 4, to separate out lead tetrachloride. This series of reactions is conducted at 0 °C. The following equations illustrate the reaction: PbCl 2 + 2HCl + Cl 2 → H 2 PbCl 6
The compounds are almost insoluble in water, weak acids, and (NH 4) 2 S/(NH 4) 2 S 2 solution is the key for separation of lead from analytical groups I to III elements, tin, arsenic, and antimony. The compounds dissolve in nitric and hydrochloric acids, to give elemental sulfur and hydrogen sulfide, respectively. [ 7 ]
Neodymium(II) chloride adopts the PbCl 2 structure. Each Nd 2+ ion is coordinated by nine Cl − ions in a tricapped trigonal prismatic arrangement. Seven of the Nd-Cl distances are in the range 2.95-3.14 Å while two are longer at 3.45 Å. [4] [5]
Addition of hydrogen sulfide or sulfide salts to a solution containing a lead salt, such as PbCl 2, gives a black precipitate of lead sulfide. Pb 2+ + H 2 S → PbS↓ + 2 H + This reaction is used in qualitative inorganic analysis. The presence of hydrogen sulfide or sulfide ions may be tested using "lead acetate paper."
And as an alternate interpretation (given that the back cover alludes to "old habits die screaming,") a Black Dog is also a symbol (in folklore!) of impending death.
Cotunnite is the natural mineral form of lead(II) chloride (PbCl 2). Unlike the pure compound, which is white, cotunnite can be white, yellow, or green. The density of mineral samples spans range 5.3–5.8 g/cm 3. The hardness on the Mohs scale is 1.5–2. The crystal structure is orthorhombic dipyramidal and the point group is 2/m 2/m 2/m.