Lead, carbonate protoxid

Oxids.—Lead Monoxid—Protoxid—Hassicot—Litharge —Plum-bi oxidum (XT. S. Br.)—PbO—222.9—is prepared by heating Pb, or its carbonate, or nitrate, in air. If the product have been fused, it is litharge if not, massicot. It forms copper-colored, mica-like plates, or a yellow powder or crystallizes, from its solution in soda or potash, in white, rhombic dodecahedra, or in rose-colored cubes. It fuses near a red heat, and volatilizes at a Avhite heat sp. gr. 9.277-9.5. It is sparingly soluble in HaO, forming an alkaline solution. 

Lead Oxide, Yellow, or Litharge (Lead Monoxide, Lead Protoxide or Plumbous Oxide). PbO, mw 223.21, yellow to yellowish-red, heavy, odorless pdr or minute, cryst scales mp 888°, bp (vol at red heat) d 9.53g/cc insol in w, ale sol in acet ac, dil nitric acid, in warm solns of fixed alkali hydroxides. It may be prepd in the lab by heating Pb nitrate, carbonate or hydroxide commercially, it is made by heating Pb to a temp considerably above its mp and continually skimming off the litharge produced. It is used in some primer compns... 

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