The Element Lithium
Introduction to Lithium
Lithium takes its place as the third element on the periodic table of elements, situated just below hydrogen and to the left of beryllium. It is the first metal on the table (excluding the rare metallic hydrogen) and it derives its name from the Greek word “lithos” meaning “stone”. Many modern technologies use lithium and it has proven pivotal to the development of the 21st-century economy.
Ten Interesting Facts about Lithium
- Scissors can cut through this soft element
- Lithium reacts with oxygen in the air quickly, becoming dark grey or black
- Grease containing lithium remains thick at high temperatures, whereas other greases become liquid. This makes it useful for automobile accessories
- 7Up soda contained lithium citrate, a mood-stabilizing drug, until 1950
- In a battery, lithium produces 3+ volts, more than any other metal
- Lithium is very lightweight, making it useful for vehicle components
- Lithium is the least dense metal at standard conditions
- There are no natural deposits of pure lithium
- Lithium salts have been found to have a strong antidepressant effect
- Aluminum products are often cut with lithium to reduce weight
- 6Li and 7Li are the two isotopes of lithium
In the Periodic Table
Under hydrogen and after helium, Lithium, with the atomic symbol Li and an atomic number of 3, lies on group 1 of the periodic table. It belongs to an elemental family known as alkali metals, which include sodium and potassium. Like those sibling elements, Li has just one valence electron.
Its electronegativity reads as 0.98 on the Pauling scale. A typical electron configuration for Li is 1s22s1.
In the Human Body
Human nutrition does not require lithium as a trace mineral, but it has been used in various pharmaceutical applications over the last 70 years. Starting in 1949, salts such as lithium carbonate became an active ingredient in treatments for bipolar disorders as well as schizophrenia, with mixed results.
Alloys of Lithium
The most common alloy is the aluminum-lithium alloy, which has numerous industrial applications. Aluminum-lithium alloys find use in vehicle frames, such as in planes, trains, and automobiles. Since lithium is the least dense metal, it is very practical for creating lightweight vehicle components. Lighter vehicles can better maximize fuel efficiency. Another compound, lithium oxide, aids in the manufacturing of glass ceramics.
Applications in the Modern World
The most prominent application of Lithium today is with electronics, specifically lithium-ion batteries. These batteries see their development in the early 1980s. A carbon-based negative electrode and a metal-oxide-based positive electrode compose these batteries. Each electrode can switch between acting as an anode or acting as a cathode, depending on the direction of the current flow through the cell. Lithium-ion batteries represent a revolution in electrochemistry. They are longer-lasting, faster charging, and more energy-dense than traditional batteries. Nearly all portable electronic devices, as well as power tools and electric automobiles, use these modern batteries.
When and how was lithium discovered?
Around the 1800s, Brazilian chemist José Banifácio de Andrada discovered the mineral petalite in a mine in Sweden. Petalite was recognized as the first mineral found to contain lithium. However, the element lithium was not properly isolated until 17 years later when Swedish chemist Johan August Arfwedson performed a chemical analysis on petalite ore. He observed this new element to form compounds in a similar fashion to sodium and potassium, hinting as to its eventual placement on the periodic table.
Where is lithium present in the universe?
Recent NASA research suggests that most of the lithium present on earth originated in distant stars. More specifically, from a stellar event known as a classical novae, or when a small star collapses under the gravity of a larger star. Funded by a grant from NASA, researchers at Arizona State University showed that most of the lithium in the universe originated via the nuclear reactions which power these novae. It is estimated that approximately 97% of the lithium on earth trace back to these massive interstellar explosions!
On earth, lithium resides in rocks, water, and biological tissue. It is present in the earth’s crust at approximately 0.003%.
Compounds, Reactions, Oxidation States, Isolation
Lithium is the only metal that will react with nitrogen in the air to form nitrides. In the air, it reacts with oxygen, tarnishing the metal into a dull gray color. When lithium floats in water, it reacts, stealing the oxygen from the water, releasing bubbles of hydrogen in the process.
Lithium has a charge/oxidation state of +1. Naturally, it has a tendency to form compounds with anions with a charge of -1. It can also, however, form compounds with other types of anions when multiple lithium atoms are present, so long as the total charge of the compound sums to zero.
Lithium Bicarbonate (LiHCO3)
The active compound in drugs used to treat bipolar disorders, manic issues, and depression. It has been studied for decades as a mood enhancer.
Lithium Hydride (LiH)
LiH acts as a precursor compound for the synthesis of most lithium compounds. This form of hydrogen helps stabilize and store rocket fuel.
Lithium Phosphate (Li3PO4)
Acts as an electrolyte in the creation of high-performance batteries.
Lithium Oxide (Li2O)
Used as a flux in ceramic glazes. When used with copper, it can generate a blue color.
Lithium Chromate (Li2CrO4)
Has a wide variety of uses, including batteries, wood preservatives, and metal corrosion inhibition.
Lithium Chloride (LiCl)
LiCl is extremely water-soluble and is one of the most hygroscopic materials known, meaning it readily absorbs moisture/humidity from the air. This makes it very valuable in the construction of air conditioners.
Lithium Bromide (LiBr)
Similar to its cousin LiCl, LiBr is highly hygroscopic, but not quite as water-soluble. Large-scale industrial drying systems use this compound.
Lithium Stearate (C18H35LiO2)
Classified as a soap, this compound makes for a great all-purpose mechanical lubricant, particularly effective at higher temperatures.
Lithium Phosphide (Li3P)
This compound finds its use as a semiconductor in lasers and other high frequency, high power electronics.
Isolation of Lithium
Lithium carbonate is often extracted from brines deep beneath salt lakes. It is then mixed with ions that purify the brine, then it is left to evaporate, often for months at a time. Isolated lithium in and of itself is not very useful, so it is typically distilled down to lithium chloride, which is then used in industry.
Physical Properties of Lithium
Lithium is a silvery-white soft metal with similar malleability to sodium.
- Symbol: Li
- Melting Point (Celsius): 180.5
- Boiling Point (Celsius): 1342
- Density (g x cm3): 0.534
- Atomic Mass: 6.94 u
- Electronegativity (Pauling scale): 0.98
- Classification: Alkali Metal
- Crustal Abundance: 0.0017%
- Electron Configuration: 1s22s1
- Key Isotopes: Li-6, Li-7
- Found: Naturally in minerals lepidolite, spodumene
- Toxicity: When present in the body at levels north of 2.0 mEq/L
Where can I buy elemental lithium?
You can buy this lively element on Amazon, Ebay or through online element stores like Luciteria. It costs around $3-12 per gram. Mineral oil surrounds the element in packaging.