Industrial production of the metal itself is reported to be about tonnes a year, and this is produced by the electrolysis of molten lithium chloride and potassium chloride in steel cells at temperatures of o C.
Lithium is moderately toxic as discovered in the s when patients were given lithium chloride as a salt substitute. However, in small doses it is prescribed as a treatment for manic depression now called bipolar disorder. Its calming effect on the brain was first noted in , by an Australian doctor, John Cade, of the Victoria Department of Mental Hygiene.
He had injected guinea pigs with a 0. Cade then gave his most mentally disturbed patient an injection of the same solution. The man responded so well that within days he was transferred to a normal hospital ward and was soon back at work. Other patients responded similarly and lithium therapy is now used all around the world to treat this mental condition.
How it works is still not known for certain, but it appears to prevent overproduction of a chemical messenger in the brain. Lithium is used commercially in various ways. Lithium oxide goes into glass and glass ceramics. Lithium metal goes into alloys with magnesium and aluminium, and it improves their strength while making them lighter. Magnesium-lithium alloy is used in protective armour plating and aluminium-lithium reduces the weight of aircraft thereby saving fuel.
Lithium stearate, made by reacting stearic acid with lithium hydroxide, is an all-purpose high-temperature grease and most greases contain it. It will even work well at temperatures as low as o C and has been used for vehicles in the Antarctic. Lithium batteries which operate at 3 volts or more are used in devices where compactness and lightness are all-important. They are implanted to supply the electrical energy for heart pacemakers.
They function with lithium as the anode, iodine as the solid electrolyte, and manganese oxide as the cathode — and they have a lifespan of ten years. This longevity has been extended to lithium batteries of the more common 1. Lithium is a soft, silvery-white, metal that heads group 1, the alkali metals group, of the periodic table of the elements. It reacts vigorously with water. Storing it is a problem. It cannot be kept under oil, as sodium can, because it is less dense and floats.
Today, larger amounts of the metal are obtained through the electrolysis of lithium chloride LiCl. Lithium is not found free in nature and makes up only 0. Many uses have been found for lithium and its compounds. Lithium has the highest specific heat of any solid element and is used in heat transfer applications. It is used to make special glasses and ceramics, including the Mount Palomar telescope's inch mirror.
Lithium is the lightest known metal and can be alloyed with aluminium , copper , manganese , and cadmium to make strong, lightweight metals for aircraft.
Lithium hydroxide LiOH is used to remove carbon dioxide from the atmosphere of spacecraft. Lithium, atomic number 3, is an element of many uses. It's used in the manufacture of aircraft and in certain batteries. It's also used in mental health: Lithium carbonate is a common treatment of bipolar disorder , helping to stabilize wild mood swings caused by the illness. Lithium has a flashy discovery story — literally. The mineral is white to gray, but when thrown into fire, it flares bright crimson.
In , Swedish chemist Johan August Arfwedson discovered that petalite contained a previously unknown element. He wasn't able to isolate the metal entirely, but he did isolate one of its salts. The name, lithium, comes from "lithos," the Greek word for "stone. It took until for someone to isolate lithium: British chemist Augustus Matthiessen and German chemist Robert Bunsen ran a current through lithium chloride to separate the element.
Lithium is a special metal in many ways. It's light and soft — so soft that it can be cut with a kitchen knife and so low in density that it floats on water. It's also solid at a wide range of temperatures, with one of the lowest melting points of all metals and a high boiling point.
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