Lead dissolves slowly in cold alkalis to form plumbites. Pb II reacts with hydroxide forming lead II oxide. Lead II is precipitated by chromate under acidic conditions. Lead reacts vigorously with fluorine, F 2 , at room temperature, and chlorine, Cl 2 , when heated, forming the corresponding lead II halides [8].
In concentrated hydrochloric acid, the chloride precipitate is dissolved. This property helps to explain the long popularity of lead for the lining of pipes designed to carry many different kinds of liquids. From its position in a table of electrode potentials, one would expect lead to replace hydrogen from acids. But the difference in electrode potentials between the two elements is so small 0. The element does tend to react with oxygen-containing acids more readily, but only because of oxidation that may take place at the same time.
The federal government finally decided that tetraethyl lead was too dangerous to use in gasoline. By , the use of this compound had been banned by all governments in North America. Other uses of lead have not declined. The best example is lead storage batteries. A lead storage battery is a device for converting chemical energy into electrical energy. Almost every car and truck has at least one lead storage battery. But no satisfactory substitute for it has been found. About 87 percent of all lead produced in the United States now goes to the manufacture of lead storage batteries.
In addition to cars and trucks, these batteries are used for communication networks and emergency power supplies in hospitals, and in forklifts, airline ground equipment, and mining vehicles. A small percentage of lead is used to make lead compounds. Although the amount of lead is small, the variety of uses for these compounds is large. Some examples of important lead compounds are:.
The health effects of lead have become much better understood since the middle of the 20th century. At one time, the metal was regarded as quite safe to use for most applications. Now lead is known to cause both immediate and long-term health problems, especially with children. It is toxic when swallowed, eaten, or inhaled. Young children are most at risk from lead poisoning. Some children have a condition known as pica.
They have an abnormal desire to eat materials like dirt, paper, and chalk. Children with pica sometimes eat paint chips off walls. At one time, many interior house paints were made with lead compounds. Thus, crawling babies or children with pica ran the risk of eating large amounts of lead and being poisoned. Some symptoms of lead poisoning include nausea, vomiting, extreme tiredness, high blood pressure, and convulsions spasms. Over a long period of time, these children often suffer brain damage.
They lose the ability to carry out normal mental functions. Other forms of lead poisoning can also occur. For example, people who work in factories where lead is used can inhale lead fumes. The amount of fumes inhaled at any one time may be small.
But over months or years, the lead in a person's body can build up. This kind of lead poisoning can lead to nerve damage and problems with the gastrointestinal system stomach and intestines. Lead causes both immediate and longterm health problems, especially with children. Today, there is an effort to reduce the use of lead in consumer products. For instance, older homes are often tested for lead paint before they are resold.
Lead paint has also been removed from older school buildings. Toggle navigation. Photo by: Dreef. Discovery and naming Lead has been around for thousands of years. Physical properties Lead is a heavy, soft, gray solid. Chemical properties Lead is a moderately active metal. Occurrence in nature The abundance of lead in the Earth's crust is estimated to be between 13 and 20 parts per million. Isotopes Four naturally occurring isotopes of lead occur. Extraction Lead is obtained from its ores by a method used with many metals.
It leaves pure lead behind: Lead obtained in this way is not very pure. A major source of lead is recycled car batteries. Uses The lead industry is undergoing dramatic change. The price of a gallon of gas F or many years, lead was regarded as a miracle chemical by the automotive industry. When tetraethyl lead breaks down, elemental lead Pb is formed: The result—with millions of cars being driven every day—was more and more lead getting into the air.
Compounds A small percentage of lead is used to make lead compounds. Health effects The health effects of lead have become much better understood since the middle of the 20th century. Other articles you might like:. Also read article about Lead from Wikipedia.
User Contributions: 1. How do u test for lead individually by yourself without taking it to a lab what at the materials and what substance reacts with lead. I have a little bit of a gasoline additive that was made years ago.
I would like to find out whats in it and can it be reproduced? Thank You! What is the composition of lead pipe used in sink and shower? Comment about this article, ask questions, or add new information about this topic: Name:.
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