About

Nihonium is a synthetic element named after the Japanese word for Japan, 'Nihon'. It holds the distinction of being the first modern element to be synthesized in an Asian country (at the RIKEN laboratory). It is a super-heavy, extremely radioactive element whose properties are largely unknown but are predicted to be similar to other group 13 elements like thallium.

Atomic Properties

Atomic Number113

Atomic Weight286.182 u

Neutrons (common)173

Electron Configuration[Rn] 5f¹⁴ 6d¹⁰ 7s² 7p¹

Full Configuration1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 6s² 6p⁶ 5f¹⁴ 6d¹⁰ 7s² 7p¹

Electrons per Shell2, 8, 18, 32, 32, 18, 3

Electronegativity1.6

Electron Affinity66.6 kJ/mol

Oxidation States+3, +1

Covalent Radius136 pm

Periodic Table Position

Group13

Period7

BlockP

Chemical SeriesPost-transition metals

Physical Properties

State at STPsolid

Crystal Structurehcp

Magnetic Orderingparamagnetic

Thermal Properties

Melting Point700 K

Boiling Point1,400 K

Heat of Fusion7.5 kJ/mol

Heat of Vaporization130 kJ/mol

Discovery

Discovered byRIKEN

Discovery Year2,004

Occurrencesynthetic

CAS Number54084-70-7

Electron Configuration

Energy

↿⇂

1s

↿⇂

2s

↿⇂

2p

↿⇂

3s

↿⇂

3p

↿⇂

4s

↿⇂

3d

↿⇂

4p

↿⇂

5s

↿⇂

4d

↿⇂

5p

↿⇂

6s

↿⇂

4f

↿⇂

5d

↿⇂

6p

↿⇂

7s

↿⇂

5f

↿⇂

6d

↿

7p

Isotopes of Nihonium

Symbol ▲	Mass (u) ▲	Abundance ▲	Half-life ▲	Decay Mode ▲
²⁸⁶Nh	286.183650	—	12 s	Alpha Decay