Lead is a chemical element in the carbon group with symbol Pb (from Latin: plumbum) and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed to air. Lead has a shiny chrome-silver luster when it is melted into a liquid.
Lead is used in building construction, lead-acid batteries, bullets and shot, weights, as part of solders, pewters, fusible alloys, and as a radiation shield. Lead has the highest atomic number of all of the stable elements, although the next higher element, bismuth, has a half-life that is so long (much longer than the age of the universe) that it can be considered stable. Its four stable isotopes have 82 protons, a magic number in the nuclear shell model of atomic nuclei.
Lead, at certain contact degrees, is a poisonous substance to animals, including humans. It damages the nervous system and causes brain disorders. Excessive lead also causes blood disorders in mammals. Like the element mercury, another heavy metal, lead is a neurotoxin that accumulates both in soft tissues and the bones. Lead poisoning has been documented from ancient Rome, ancient Greece, and ancient China.
Other articles related to "lead":
... The Beatles John Lennon – lead, harmony and backing vocals, rhythm and acoustic guitars, piano, harmonica, tambourine, handclaps 12-string lead guitar on "Eve ...
... In the human body, lead inhibits porphobilinogen synthase and ferrochelatase, preventing both porphobilinogen formation and the incorporation of iron into protoporphyrin ... Acute lead poisoning is treated using disodium calcium edetate the calcium chelate of the disodium salt of ethylene-diamine-tetracetic acid (EDTA) ... agent has a greater affinity for lead than for calcium and so the lead chelate is formed by exchange ...
... By 1795 the former Templar mills were being used for preparing lead ... Sheets of lead were placed in clay pots and submerged in urine, then heated by decaying cow dung ... The process converted the lead to lead oxide, and it was then finely ground to form a pigment for white, yellow and red lead paint ...
... The Lead has to communicate the direction of the movement to the Follow ... Traditionally, the Lead's right hand on the follow's back, near the lowest part of the shoulder-blade ... This is the strongest part of the back and the lead can easily pull the Follow's body inwards ...
... non-toxic lightfast substitute for lemon yellow pigments such as the cadmium sulfides and the lead/strontium/barium chromates ... Unlike lead chromate+lead sulfate lemon, bismuth vanadate does not readily blacken with UV exposure ...
Famous quotes containing the word lead:
“Scientific reason, with its strict conscience, its lack of prejudice, and its determination to question every result again the moment it might lead to the least intellectual advantage, does in an area of secondary interest what we ought to be doing with the basic questions of life.”
—Robert Musil (18801942)
“Events, actions arise, that must be sung, that will sing themselves. Who can doubt, that poetry will revive and lead in a new age, as the star in the constellation Harp, which now flames in our zenith, astronomers announce, shall one day be the pole- star for a thousand years?”
—Ralph Waldo Emerson (18031882)
“If all would lead their lives in love like me,
Then bloody swords and armor should not be;
No drum nor trumpet peaceful sleeps should move,
Unless alarm came from the camp of love.”
—Thomas Campion (15671620)