Lithium (from Greek lithos 'stone') is a soft, silver-white metal with symbol Li. It is the third chemical element in the periodic table. This means that it has 3 protons in its nucleus and 3 electrons around it. Its atomic number is 3. Its mass number is 6.94. It has two common isotopes, ⁶Li and ⁷Li. ⁷Li is more common. 92.5% of lithium is ⁷Li. Lithium is a soft silvery metal that is very reactive. It is used in lithium batteries and certain medicines.

Properties
Occurrence
History
Preparation
Uses
Safety
Isotopes
Related pages
Images for kids
See also

Properties

Physical properties

Lithium is one of the alkali metals. Lithium is a silvery solid metal (when freshly cut). It is very soft. Thus it can be cut easily with a knife. It melts at a low temperature. It is very light, similar to wood. It is the least dense metal and the least dense element in a solid or liquid state. It can hold more heat than any other solid element. It conducts heat and electricity easily.

Chemical properties

It will react with water, giving off hydrogen to form a basic solution (lithium hydroxide). Because of this, lithium must be stored in petroleum jelly. Sodium and potassium can be stored in oil but lithium cannot because it is so light. It will just float on the oil and not be protected by it.

Lithium also reacts with halogens. It can react with nitrogen gas to make lithium nitride. It reacts with air to make a black tarnish and then a white powder of lithium hydroxide and lithium carbonate.

Chemical compounds

See also: Category:Lithium compounds

Flame test for lithium

Lithium forms chemical compounds with only one oxidation state: +1. Most of them are white and unreactive. They make a bright red color when heated in a flame. They are a little toxic. Most of them dissolve in water. Lithium carbonate is less soluble in water than the other alkali metal carbonates like sodium carbonate.

Lithium carbonate, used in medicine
Lithium chloride, colorless crystalline solid, red flame when heated
Lithium hydroxide, strong base, used to remove carbon dioxide in spaceships
Lithium nitrate, oxidizing agent
Lithium nitride, strong base
Lithium oxide, dissolves in water to make lithium hydroxide
Lithium peroxide, reacts with water to make oxygen
LiHe
Lithium 12-hydroxystearate
Lithium acetate
Lithium aluminate
Lithium aluminium hydride
Lithium amide
Lithium aspartate
Lithium azide
Lithium beryllide
Lithium bis(trifluoromethanesulfonyl)imide
Lithium bis(trimethylsilyl)amide
Lithium borate
Lithium bromide
Lithium carbide
Lithium chlorate
Lithium citrate
Lithium cobalt oxide
Lithium cyanide
Lithium diisopropylamide
Lithium disilicate

Occurrence

It does not occur as an element in nature. It only is in the form of lithium compounds. The ocean has a large amount of lithium in it. Certain granites have large amounts of lithium. Most living things have lithium in them. There are some places where much lithium is in the salt. Some silicates have lithium in them.

History

Lithium (Greek lithos, meaning "stone") was discovered by Johann Arfvedson in 1817. In 1818, Christian Gmelin observed that lithium salts give a bright red color in flame. W.T. Brande and Sir Humphrey Davy later used electrolysis on lithium oxide to isolate the element. Lithium was first used in greases. Then nuclear weapons became a big use of lithium. Lithium was also used to make glass melt easier and make aluminium oxide melt easier in making aluminium. Now lithium is used mainly in batteries.

It was apparently given the name "lithium" because it was discovered from a mineral, while other common alkali metals were first discovered in plant tissue.

Preparation

It is made by getting lithium chloride from pools and springs. The lithium chloride is melted and electrolyzed. This makes liquid lithium and chlorine.

Uses

As an element

Its main use is in batteries. Lithium is used as an anode in the lithium battery. It has more power than batteries with zinc, like alkaline cells. Lithium ion batteries also have lithium in them, though not as an element. It is also used in heat transfer alloys. Lithium is used to make organolithium compounds. They are used for very strong bases.

It is used to make special glasses and ceramics, including the Mount Palomar telescope's 200 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.

In chemical compounds

Lithium compounds are used in some drugs known as mood stabilizers. Lithium niobate is used in radio transmitters in cell phones. Some lithium compounds are also used in ceramics. Lithium chloride can absorb water from other things. Some lithium compounds are used to make soap and grease. Lithium carbonate is used as a drug to treat manic depression disorder. Lithium carbonate is used for the treatment of bipolar disease and other mental illness conditions.

Organic chemistry

Organolithium compounds are used to make polymers and fine chemicals. Many lithium compounds are used as reagents to make organic compounds. Some lithium compounds like lithium aluminium hydride, lithium triethylborohydride, n-butyllithium and tert-butyllithium are commonly used as very strong bases called superbases.

Other uses

Lithium compounds are used as pyrotechnic colorants and oxidizers in red fireworks and flares. Lithium chloride and lithium bromide are used as desiccants for gas streams. Lithium hydroxide and lithium peroxide are used to remove carbon dioxide and purify the air in spacecrafts and submarines. Lithium hydroxide, lithium peroxide and lithium perchlorate are used in oxygen candles that supply submarines with oxygen.

Lithium aluminum hydride can also be used as a solid fuel by itself. Lithium hydride that contains lithium-6 is used in thermonuclear weapons.

Safety

Lithium reacts with water, making irritating smoke and heat. It is not as dangerous as the other alkali metals. Lithium hydroxide is very corrosive.

Isotopes

There are 5 isotopes of Lithium having respectively 2, 3, 4, 5 and 6 neutrons in the nucleus. The most common isotope in nature is ₃Li⁷ which makes up 92.58 % of the total. The second isotope which is widely available is ₃Li⁶ which makes up 7.42 % of the total. The other 3 isotopes exist in very small quantities. The atomic mass of Lithium is 6.939.

Alkaline earth metals

Poor metals

Other nonmetals

Images for kids

Lithium ingots with a thin layer of black nitride tarnish
Lithium floating in oil
Nova Centauri 2013 is the first in which evidence of lithium has been found.
Johan August Arfwedson is credited with the discovery of lithium in 1817
Hexameric structure of the n-butyllithium fragment in a crystal
Scatter plots of lithium grade and tonnage for selected world deposits, as of 2017
The launch of a torpedo using lithium as fuel
Lithium deuteride was used as fuel in the Castle Bravo nuclear device.