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Compounds of lead exist in two main oxidation states: +2 and +4. The former is more common. Inorganic lead(IV) compounds are typically strong oxidants or exist only in highly acidic solutions. ==Chemistry== Various oxidized forms of lead are easily reduced to the metal. An example is heating PbO with mild organic reducing agents such as glucose. A mixture of the oxide and the sulfide heated together will also form the metal. : 2 PbO + PbS → 3 Pb + SO2 Metallic lead is attacked (oxidized) only superficially by air, forming a thin layer of lead oxide that protects it from further oxidation. The metal is not attacked by sulfuric or hydrochloric acids. It dissolves in nitric acid with the evolution of nitric oxide gas to form dissolved Pb(NO3)2. : 3 Pb + 8 H+ + 8 → 3 Pb2+ + 6 + 2 NO + 4 H2O When heated with nitrates of alkali metals, metallic lead oxidizes to form PbO (also known as litharge), leaving the corresponding alkali nitrite. PbO is representative of lead's +2 oxidation state. It is soluble in nitric and acetic acids, from which solutions it is possible to precipitate halide, sulfate, chromate, carbonate (PbCO3), and basic carbonate ( salts of lead. The sulfide can also be precipitated from acetate solutions. These salts are all poorly soluble in water. Among the halides, the iodide is less soluble than the bromide, which, in turn, is less soluble than the chloride. Lead(II) oxide is also soluble in alkali hydroxide solutions to form the corresponding plumbite salt.〔 : PbO + 2 OH− + H2O → Chlorination of plumbite solutions causes the formation of lead's +4 oxidation state. : + Cl2 → PbO2 + 2 Cl− + 2 H2O Lead dioxide is representative of the +4 oxidation state, and is a powerful oxidizing agent. The chloride of this oxidation state is formed only with difficulty and decomposes readily into lead(II) chloride and chlorine gas. The bromide and iodide of lead(IV) are not known to exist.〔 Lead dioxide dissolves in alkali hydroxide solutions to form the corresponding plumbates.〔 : PbO2 + 2 OH− + 2 H2O → Lead also has an oxide with mixed +2 and +4 oxidation states, red lead (), also known as ''minium''. Lead readily forms an equimolar alloy with sodium metal that reacts with alkyl halides to form organometallic compounds of lead such as tetraethyllead. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Compounds of lead」の詳細全文を読む スポンサード リンク
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