Lesson 4 of 13 · 6 min
Naming elements with Z above 100
NCERT §3.4
Two laboratories made element 104 and gave it two different names. How do you name an element before anyone agrees who found it?
The lesson in notes
In short
New heavy elements are so unstable that sometimes only a few atoms are made, in a handful of laboratories. Rival claims followed: for element 104 the Americans proposed rutherfordium and the Soviets kurchatovium.
IUPAC's rule: until a discovery is confirmed and named, the element gets a systematic name built from its digits. Roots: 0 nil, 1 un, 2 bi, 3 tri, 4 quad, 5 pent, 6 hex, 7 sept, 8 oct, 9 enn.
Join the roots in the order of the digits and add -ium. The temporary symbol has three letters, the first letter of each root, with the first capitalised.
Example: Z = 120 → un + bi + nil + ium = unbinilium, symbol Ubn. Z = 101 → unnilunium (Unu); Z = 118 → ununoctium (Uuo).
A final name and symbol follow a vote among IUPAC delegates of the member countries. They may recall the place of discovery (a country or one of its states) or honour a well-known scientist.
Elements up to Z = 118 have been discovered and all have official IUPAC names, for example 101 mendelevium (Md), 104 rutherfordium (Rf), 106 seaborgium (Sg), 113 nihonium (Nh), 114 flerovium (Fl), 117 tennessine (Ts) and 118 oganesson (Og).