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2 Pb(NO 3) 2 → 2 PbO + 4 NO 2 + O 2 PbCO 3 → PbO + CO 2. PbO is produced on a large scale as an intermediate product in refining raw lead ores into metallic lead. The usual lead ore is galena (lead(II) sulfide). At a temperature of around 1,000 °C (1,800 °F) the sulfide is converted to the oxide: [5] 2 PbS + 3 O 2 → 2 PbO + 2 SO 2
Lead(II,IV) oxide is prepared by calcination of lead(II) oxide (PbO; also called litharge) in air at about 450–480 °C: [5] 6 PbO + O 2 → 2 Pb 3 O 4. The resulting material is contaminated with PbO. If a pure compound is desired, PbO can be removed by a potassium hydroxide solution: PbO + KOH + H 2 O → K[Pb(OH) 3]
Lead(II) sulfate is poorly soluble, as can be seen in the following diagram showing addition of SO 2− 4 to a solution containing 0.1 M of Pb 2+. The pH of the solution is 4.5, as above that, Pb 2+ concentration can never reach 0.1 M due to the formation of Pb(OH) 2. Observe that Pb 2+ solubility drops 10,000 fold as SO 2− 4 reaches 0.1 M.
2 Pb 12 O 17 → 8 Pb 3 O 4 + O 2 2 Pb 3 O 4 → 6 PbO + O 2. The stoichiometry of the end product can be controlled by changing the temperature – for example, in the above reaction, the first step occurs at 290 °C, second at 350 °C, third at 375 °C and fourth at 600 °C. In addition, Pb 2 O 3 can be obtained by decomposing PbO 2 at 580 ...
As well as an anhydrous form, a monohydrate (PbC 2 O 4 •H 2 O), [5] a dihydrate (PbC 2 O 4 •2H 2 O) and a trihydrate (PbC 2 O 4 •3H 2 O) are known. The dihydrate is from the orthorhombic crystal system, with space group Pnam (number 62), with unit cell dimensions: a = 9.053 Å b = 8.036 Å and c = 7.834 Å.
[4] [5] Plumbate salts contain either the hydrated hexahydroxoplumbate(IV) or plumbate anion [Pb(OH) 6] 2−, or the anhydrous anions PbO 2− 3 (metaplumbate) or PbO 4− 4 (orthoplumbate). [4] For example, dissolving PbO 2 in a hot, concentrated aqueous solution of potassium hydroxide forms the potassium hexahydroxoplumbate(IV) salt K 2 [Pb ...
Typical reactions are: [5] R 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 ...
Lead(II) chromate can be produced by treating sodium chromate with lead salts such as lead(II) nitrate or by combining lead(II) oxide with chromic acid.. Related lead sulfochromate pigments are produced by the replacement of some chromate by sulfate, resulting in a mixed lead-chromate-sulfate compositions Pb(CrO 4) 1−x (SO 4) x.