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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
24 PbO 2 → 2 Pb 12 O 19 + 5 O 2 Pb 12 O 19 → Pb 12 O 17 + O 2 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.
The alpha allotrope is red-colored and has the Pb–O distance of 230 pm; the beta allotrope is yellow-colored and has the Pb–O distance of 221 and 249 pm (due to asymmetry). [5] Thanks to the similarity, both allotropes can exist under standard conditions (beta with small (10 −5 relative) impurities, such as Si, Ge, Mo, etc.).
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]
The capped square antiprismatic anion [Pb 9] 4− from [K(18-crown-6)] 2 K 2 Pb 9 ·(en) 1.5 [82] Some lead compounds exist in formal oxidation states other than +4 or +2. Lead(III) may be obtained, as an intermediate between lead(II) and lead(IV), in larger organolead complexes; this oxidation state is not stable, as both the lead(III) ion and ...
[Pb 5] 2−. Plumbide is an anion of lead atoms. There are three plumbide anions, written as Pb −, Pb 2− and Pb 4− with 3 oxidation states, -1, -2 and -4, respectively.A plumbide can refer to one of two things: an intermetallic compound that contains lead, or a Zintl phase compound with lead as the anion.
Lead (82 Pb) has four observationally stable isotopes: 204 Pb, 206 Pb, 207 Pb, 208 Pb. Lead-204 is entirely a primordial nuclide and is not a radiogenic nuclide.The three isotopes lead-206, lead-207, and lead-208 represent the ends of three decay chains: the uranium series (or radium series), the actinium series, and the thorium series, respectively; a fourth decay chain, the neptunium series ...
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.