Lead

__ Lead __



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Fast Facts
Symbol: Pb Atomic Number: 82 Atomic Mass: 207.2 Density: 11.34 g State at r.t.p.: Solid Melting Point: 327.46 °C Boiling Point: 1749 °C Appearance: Blue-silver when freshly cut. When it is exposed to the air, it turns dull gray. Group: 14 Period: 6 Isotopes: Pb-178, Pb-179, Pb-180, Pb-181, Pb-182, Pb-183, Pb-184, Pb-185, Pb-186, Pb-187, Pb-188, Pb-189, Pb-190, Pb-191 ,Pb-192, Pb-193, Pb-194, Pb-195, Pb-196, Pb-197, Pb-198, Pb-199, Pb-200, Pb-201, Pb-202, Pb-203, Pb-204, Pb-205, Pb-206, Pb-207, Pb-208, Pb-209, Pb-210, Pb-211, Pb-212, Pb-213, Pb-214, Pb-215



History
Lead was one of the earliest discovered metals. The oldest found lead object in an Egyptian figurine. It dates back to 4000 B.C. Lead was used by the ancient Romans as early as 3000 B.C. They used it for pipes and plumbing, food and wine containers, decorative objects, and cooking pots. The Romans used lead to sweeten their food and hold their wine. Lead is the only metal used for this because it gave the wine a sweet taste. Other metals made it bitter. It has also been used in early cosmetics, paints, pigments, and glazes. Because of the wide usage of lead, many people became poisoned.

Lead Poisoning
Lead poisoning is a risk for everyone. However, unborn babies and small children are more at risk. Every year about 310,000 children from the ages 1 to 5 are found to have lead in their blood. Small children often do not show signs of lead poisoning, so they should be checked for lead in their bloodstream every year. When symptoms are present, they include: irritable behavior, eating things such as dirt or paint chips, difficulty concentrating, headaches, loss of appetite, weight loss, fatigue, abdominal pain, nausea, constipation, pale skin, metallic taste in mouth, muscle and joint pain, and seizures. Lead can enter the body in different ways. It can be eaten, breathed in, and absorbed through the skin. In the bloodstream, lead damages red blood cells and prevents them from carrying the necessary amount of oxygen to the organs. Lead in bones prevents calcium absorption, which causes them to become weak. Lead also damages brain cells, the nervous system, and hearing. It can cause digestive problems and stunted growth.

**Uses**
Lead has been used in all sorts of things throughout history. Lead has often been used in white paint. The lead gave paint the white color, but after awhile of air exposure, it turned black. Lead also helped paint stick to the wall. Certain lipsticks have also used lead to help it stick. Pipes and plumbing have been made out of lead for a long time, but recently have had to been replaced. Lead pipes would contaminate water and people would be poisoned. Construction materials have also been made out of lead. Batteries made out of lead acid are very important. they can be recharged and are used for almost everything that requires a battery.

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