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Lead(II) oxide, also called lead monoxide, is the inorganic compound with the molecular formula Pb O. PbO occurs in two polymorphs : litharge having a tetragonal crystal structure , and massicot having an orthorhombic crystal structure .
Lead sesquioxide, Pb 2 O 3, which is a lead (II,IV) oxide as well (lead(II) metaplumbate(IV) [Pb 2+][PbO 2− 3]), reddish yellow Pb 12 O 19 , monoclinic, dark-brown or black crystals The so-called black lead oxide , which is a mixture of PbO and fine-powdered Pb metal and used in the production of lead–acid batteries .
Molecular weight (M.W.) (for molecular compounds) and formula weight (F.W.) (for non-molecular compounds), are older terms for what is now more correctly called the relative molar mass (M r). [8] This is a dimensionless quantity (i.e., a pure number, without units) equal to the molar mass divided by the molar mass constant .
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(NO 3) 2. 3 Pb + 8 H + + 8 NO − 3 → 3 Pb 2+ + 6 NO − ...
According to the FDA, the acceptable levels of lead in baby food are as follows: 10 parts per billion (ppb) for fruits, vegetables (excluding single-ingredient root vegetables), mixtures ...
Nitric acid dissolves the lead(II) oxide component, leaving behind the insoluble lead(IV) oxide: Pb 3 O 4 + 4 HNO 3 → PbO 2 + 2 Pb(NO 3) 2 + 2 H 2 O. With iron oxides and with elemental iron, lead(II,IV) oxide forms insoluble iron(II) and iron(III) plumbates, which is the basis of the anticorrosive properties of lead-based paints applied to ...
The World Health Organization (WHO) specifically notes that there is "no known safe blood lead concentration," and that even blood lead concentrations as low as 3.5 µg/dL (micrograms per ...
Few inorganic lead(IV) compounds are known. They are only formed in highly oxidizing solutions and do not normally exist under standard conditions. [76] Lead(II) oxide gives a mixed oxide on further oxidation, Pb 3 O 4. It is described as lead(II,IV) oxide, or structurally 2PbO·PbO 2, and is the best-known mixed valence lead compound.