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In the gas phase, PbCl 2 molecules have a bent structure with the Cl–Pb–Cl angle being 98° and each Pb–-Cl bond distance being 2.44 Å. [7] Such PbCl 2 is emitted from internal combustion engines that use ethylene chloride-tetraethyllead additives for antiknock purposes.
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 ]
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
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.
4 Pb + HCl → R 3 PbCl + RH R 4 Pb + SO 2 → R 3 PbO(SO)R R 3 PbCl + 1/2Ag 2 O (aq) → R 3 PbOH + AgCl R 2 PbCl 2 + 2 OH − → R 2 Pb(OH) 2 + 2 Cl −. R 2 Pb(OH) 2 compounds are amphoteric. At pH lower than 8 they form R 2 Pb 2+ ions and with pH higher than 10, R 2 Pb(OH) 3 − ions. Derived from the hydroxides are the plumboxanes: 2 R 3 ...
Phosgenite is a rare mineral consisting of lead carbonate chloride, (PbCl) 2 CO 3. The tetragonal crystals are prismatic or tabular in habit: they are usually colorless and transparent, and have a brilliant adamantine lustre. Sometimes the crystals have a curious helical twist about the tetrad or principal axis. The hardness is 3 and the ...
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.
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]