Characteristics of lithium
Lithium, of symbol Li, is the third lightest element in our universe. It has atomic number three, that to say, it has 3 protons (and neutrons) in its nucleus, with three electrons orbiting them. Lithium is a highly flammable element, toxic (except in small quantities), and odourless. A particularity of this metal is that it is highly reactive with water. It has a silver-white colour.
In standard conditions, this element is the lightest metal and solid, and it is a good conductor of heat and electricity. Lithium is one of the six alkaline metals, and it can be cut with a knife. In comparison to other metals lithium has a low melting point (180ºC), but it has the highest melting and boiling points (1330ºC) of all the alkali metals. Exposed to extremely low temperatures it becomes a superconductive material.
Lithium is an extremely reactive and corrosive element. Contact with the skin can provoke burnings and blisters. Moreover, prolonged exposure to this toxic material can lead to damage to the lungs.
Abundance and formation
Due to its high reactivity, lithium doesn’t exist freely in nature. We normally find this material inside molecules of diverse minerals. Lithium constitutes approximately 0.002% of the Earth’s crust.
At the moment of the Big Bang, a small part of the chemical elements that exist today were produced. Mainly hydrogen and helium were produced, which represented more than 99% of the elements that had been produced. However, the next element that was produced at the moment of the Big Bang was lithium. So, the majority of lithium that exists nowadays in our universe comes from the first instants of the latter.
Discovery and history
Lithium was discovered in 1817 by the Swedish chemist Johan August Arfvedson from a mineral named petalite. However, it wasn’t until 4 years had passed that this element could be isolated in a pure form by William Thomas Brande, through the process of electrolysis of lithium oxide.
The name lithium comes from the Greek word “lythos”, which means stone. This is due to that this metal was discovered in a rock, in comparison to other metals such as potassium and sodium, which were discovered in plants and animals, respectively.
Uses of this element
Lithium is a material that has a great variety of uses and commercial applications. One of the broadest uses that we give to this element is the production of batteries for a varied range of devices. These batteries are rechargeable and have a big energy density. Some of the other uses of lithium are the following:
- Lithium is used in the production of glasses and ceramics of high quality.
- This element is also used in metallurgy processes, for example in the fabrication of alloys of different metals. This makes them more resistant and lightweight.
- Lithium chloride is one of the most hygroscopic (it has the capacity to absorb moisture from the air) known materials, and is used in air conditioning and industrial drying systems.
- Lithium-6 is used in the production of tritium and as a neutron absorber in nuclear fusion reactions.
- The salts of this material are used to treat diverse mental disorders, including bipolar disorder, depression and schizoaffective disorder, even if the consequences on the brain are not really understood.
An isotope is an atom that has a different number of electrons in comparison to its original composition.
Lithium has 11 known isotopes, of which only two are stable: the lithium-6 (6Li) and the lithium-7 (7Li). These two isotopes have a natural abundance of 7.9% and 92.41%, respectively. The rest of the isotopes have been formed artificially, are extremely unstable and disintegrate in extremely short periods of time. When these isotopes disintegrate, they convert into other isotopes, of different elements, as beryllium or hydrogen.