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Cut glass wine glass made of lead glass. Lead glass, commonly called crystal, is a variety of glass in which lead replaces the calcium content of a typical potash glass. [1] Lead glass contains typically 18–40% (by mass) lead(II) oxide (PbO), while modern lead crystal, historically also known as flint glass due to the original silica source, contains a minimum of 24% PbO. [2]
Lead's close-packed face-centered cubic structure and high atomic weight result in a density [24] of 11.34 g/cm 3, which is greater than that of common metals such as iron (7.87 g/cm 3), copper (8.93 g/cm 3), and zinc (7.14 g/cm 3). [25] This density is the origin of the idiom to go over like a lead balloon.
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) in air, the sulfide converted to the oxide: [4] 2 PbS + 2 O 2 → 2 PbO + 2 SO 2
Lead oxide is the traditional low temperature flux used for crystal glass, but it is now avoided because it is toxic even in small quantities. It is being replaced by other substances, especially boron and zinc oxides. [3] In clay bodies a flux creates a limited and controlled amount of glass, which works to cement crystalline phases together.
Yet another method is oxidative annealing of white lead: 3 Pb 2 CO 3 (OH) 2 + O 2 → 2 Pb 3 O 4 + 3 CO 2 + 3 H 2 O. In solution, lead(II,IV) oxide can be prepared by reaction of potassium plumbate with lead(II) acetate, yielding yellow insoluble lead(II,IV) oxide monohydrate Pb 3 O 4 ·H 2 O, which can be turned into the anhydrous form by ...
Lead was used for roof covering material and water supply and waste pipes. The Latin name for lead is plumbum, thus plumbing. Romans also made use of glass in construction with colored glass in mosaics and clear glass for windows. Glass came to be fairly commonly used in windows of public buildings. [2]
Lead and cadmium were found in a majority of the protein powders that were tested. There is no safe level of lead, which has been linked to developmental disorders and high blood pressure.
Leaded glass may refer to: Lead glass , potassium silicate glass which has been impregnated with a small amount of lead oxide in its fabrication Lead came glasswork , glass panels made by combining multiple small pieces of glass, which may be stained, textured or beveled, with cames or copper foil