ElementsWhat is nihonium?
Nihonium is a radioactive element made in particle accelerators. Its name was approved in 2016.
What is nihonium used for?
Research only.
Where the name comes from
From Nihon, a Japanese name for Japan. It was the first element discovered in Asia.
Key facts
- Symbol
- Nh
- Atomic number
- 113
- Atomic mass
- 286.182 u
- Family
- Post-transition metal
- Period
- 7
- Group
- 13
- Block
- p
- State at room temperature
- Solid (expected)
- Melting point
- not measured
- Boiling point
- not measured
- Density
- not measured
- Electrons per shell
- 2, 8, 18, 32, 32, 18, 3
- Electron configuration
- [Rn]5f14 6d10 7s2 7p1
- Common oxidation states
- not known
- Electronegativity (Pauling)
- no value
- First ionisation energy
- not measured
- Electron affinity
- no value
- Atomic radius (van der Waals)
- no value
- Discovered
- 2004
Place in the periodic table
Nihonium is element number 113. It sits in period 7 (row 7) of the periodic table, in group 13 (column 13), and belongs to the p-block. Just before it comes copernicium (112), and just after it comes flerovium (114). In the same column, thallium is above it. Elements in one column tend to behave alike.
Family: Post-transition metals.
Physical properties
Too few atoms of nihonium have been made to measure its bulk properties. It is expected to be a solid at room temperature.
Inside the atom
An atom of nihonium has 113 protons in its nucleus and, when neutral, 113 electrons around it. The electrons are arranged in 7 shells: 2, 8, 18, 32, 32, 18, 3. The outermost shell holds 3 electrons. Written in full, the electron configuration is [Rn]5f14 6d10 7s2 7p1 (predicted).
One mole of nihonium weighs 286.182 grams, so a single gram contains about 2.10 × 1021 atoms.
The ring picture is a simple model that only counts the electrons in each shell. Real atoms do not look like this.
Next steps
- Work out the weight of a compound that contains nihonium with the molar mass calculator.
- Compare it with every other element in the sortable list.
- Test yourself with the symbol quiz.
Figures on this page are from PubChem (U.S. National Library of Medicine), as downloaded on 11 November 2026. See About and data sources.