How a new chemical element gets its name
A new element is named by the people who made it, but only after an international panel agrees they made it, and only from a short list of allowed sources. Until then it carries a temporary name built from its atomic number. Element 118 was ununoctium for years before it became oganesson in 2016.
Step one: proving the element exists
The superheavy elements are made a few atoms at a time by firing one nucleus at another, and the heaviest last well under a second. A claim of discovery is checked by a joint working party of IUPAC, the chemistry union, and IUPAP, its physics counterpart. When the party accepts a claim, it also decides which laboratory gets the credit, and with it the right to propose a name.
On 30 December 2015 IUPAC confirmed the discoveries of elements 113, 115, 117 and 118. That completed the seventh row of the periodic table.
What a name can honour
IUPAC’s rules allow five sources for a new name:
- a mythological concept or character, including an astronomical object
- a mineral or similar substance
- a place or geographical region
- a property of the element
- a scientist
The ending depends on where the element sits. Elements in groups 1 to 16, which includes the lanthanides and actinides, end in -ium. Group 17 takes -ine, like chlorine and iodine, and group 18 takes -on, like neon and argon. That rule was written into the 2016 recommendations so the two newest elements in those groups could match their neighbours, which is why element 117 is tennessine and not tennessium.
A name that has been used for one element, even unofficially, cannot later be given to a different one.
From proposal to approval
The discoverers send their proposal to IUPAC’s Inorganic Chemistry Division. If the division accepts it, the name goes out for five months of public comment before the IUPAC Council approves it. For the last four elements, the proposed names were published on 8 June 2016, the comment period closed on 8 November and the names were approved on 28 November 2016.
| NO. | NAME | HONOURS | MADE AT |
|---|---|---|---|
| 113 | Nihonium (Nh) | Nihon, one of the two Japanese names for Japan | RIKEN, Japan |
| 115 | Moscovium (Mc) | The Moscow region, home of the Dubna institute | Dubna with Oak Ridge, Vanderbilt and Livermore |
| 117 | Tennessine (Ts) | Tennessee, home of Oak Ridge and Vanderbilt | The same collaboration as 115 |
| 118 | Oganesson (Og) | The physicist Yuri Oganessian | Dubna and Livermore |
The temporary names
Since 1978 an element without an approved name has been called by its number, one root per digit, with -ium on the end whatever group it belongs to. The symbol is the first letter of each root.
| DIGIT | ROOT |
|---|---|
| 0 | nil |
| 1 | un |
| 2 | bi |
| 3 | tri |
| 4 | quad |
| 5 | pent |
| 6 | hex |
| 7 | sept |
| 8 | oct |
| 9 | enn |
So 118 was un-un-oct-ium, Uuo. Elements 119 and 120 would be ununennium (Uue) and unbinilium (Ubn) until someone makes them and the discovery is confirmed.
When two laboratories claimed the same element
The rules are strict because of what happened with elements 102 to 109. From the 1960s, the Berkeley laboratory in California and the Joint Institute for Nuclear Research in Dubna both claimed several of them and used different names. Berkeley called 105 hahnium, Dubna called it nielsbohrium, and Dubna’s kurchatovium for 104 competed with Berkeley’s rutherfordium.
IUPAC’s compromise of 1994 moved names around and drew objections, from the American Chemical Society among others. One objection to Berkeley’s seaborgium for 106 was that Glenn Seaborg was still alive. The final list was approved in 1997: rutherfordium (104), dubnium (105), seaborgium (106), bohrium (107), hassium (108) and meitnerium (109). Hahnium was dropped. Several countries outside the dispute had used kurchatovium and hahnium until then.
Elements on the Table asks for all 118 by name or symbol, and the section under the game explains the names that honour people, places and planets.