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Lead (/ l ɛ d /) is a chemical element; it has symbol Pb (from Latin plumbum) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cut, lead is a shiny gray with a hint of blue. It tarnishes to a dull gray color when exposed to ...
Lead–acid batteries lose the ability to accept a charge when discharged for too long due to sulfation, the crystallization of lead sulfate. [30] They generate electricity through a double sulfate chemical reaction. Lead and lead dioxide, the active materials on the battery's plates, react with sulfuric acid in the electrolyte to form lead ...
Lead white paint dries relatively quickly to form a strong, flexible paint film. Lead-based white is one of the oldest manufactured pigments. It was the only white pigment available to artists in appreciable quantities until the twentieth century, when zinc white and titanium white became available. [44]
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 ...
Tetraethyllead (commonly styled tetraethyl lead), abbreviated TEL, is an organolead compound with the formula Pb(C 2 H 5) 4.It was widely used as a fuel additive for much of the 20th century, first being mixed with gasoline beginning in the 1920s.
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 ...
Thomas Midgley Jr. (May 18, 1889 – November 2, 1944) was an American mechanical and chemical engineer.He played a major role in developing leaded gasoline (tetraethyl lead) and some of the first chlorofluorocarbons (CFCs), better known in the United States by the brand name Freon; both products were later banned from common use due to their harmful impact on human health and the environment.
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 .