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Its weak metallic character is illustrated by its amphoteric nature; lead and lead oxides react with acids and bases, and it tends to form covalent bonds.Compounds of lead are usually found in the 2 oxidation state rather than the 4 state common with lighter members of the carbon group.Lead is a chemical element with symbol Pb (from the Latin plumbum) and atomic number 82.It is a heavy metal that is denser than most common materials.The similarity of ionization energies is caused by the lanthanide contraction—the decrease in element radii from lanthanum (atomic number 57) to lutetium (71), and the relatively small radii of the elements after hafnium (72).This is due to poor shielding of the nucleus by the lanthanide 4f electrons.
Apart from the stable isotopes, which make up almost all lead that exists naturally, there are trace quantities of a few radioactive isotopes.
In the late 19th century, lead's toxicity was recognized, and its use has since been phased out of many applications.
Lead is a neurotoxin that accumulates in soft tissues and bones, damages the nervous system, and causes blood disorders.
Lead is soft and malleable, and has a relatively low melting point.
When freshly cut, lead is bluish-white; it tarnishes to a dull gray color when exposed to air.
Lead is easily extracted from its ores; prehistoric people in Western Asia knew of it.