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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 ...
Corrosion is a natural process that converts a refined metal into a more chemically stable oxide.It is the gradual deterioration of materials (usually a metal) by chemical or electrochemical reaction with their environment.
High-temperature corrosion is a mechanism of corrosion that takes place when gas turbines, diesel engines, furnaces or other machinery come in contact with hot gas containing certain contaminants. Fuel sometimes contains vanadium compounds or sulfates, which can form low melting point compounds during combustion.
Lead was often mixed into oil-based paints before 1978, the year lead paint was banned for residential use in the U.S. Over time, oil-based paints will crack in a distinctive alligator scale-like ...
Lead may also be harmful to the developing immune system, causing production of excessive inflammatory proteins; this mechanism may mean that lead exposure is a risk factor for asthma in children. [188] Lead exposure has also been associated with a decrease in activity of immune cells such as polymorphonuclear leukocytes. [188]
Corrosion of the external metal parts of the lead–acid battery results from a chemical reaction of the battery terminals, plugs, and connectors. Corrosion on the positive terminal is caused by electrolysis, due to a mismatch of metal alloys used in the manufacture of the battery terminal and cable connector.
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 ...
Galvanic corrosion (also called bimetallic corrosion or dissimilar metal corrosion) is an electrochemical process in which one metal corrodes preferentially when it is in electrical contact with another, in the presence of an electrolyte.