Unbiunium (Ubu)
SuperactinideStandard Atomic Weight
N/AElectron configuration
[Og] 5g¹ 8s²Melting point
N/ABoiling point
N/ADensity
N/AOxidation states
N/AElectronegativity (Pauling)
N/AIonization energy (1st)
Discovery year
N/AAtomic radius
N/AUnbiunium is the temporary systematic name for element 121, symbol Ubu. It has not been confirmed by synthesis, and all chemical data are theoretical. In extended periodic-table models it is placed just beyond elements 119 and 120, often as an early superactinide or eka-actinium-like element. Relativistic electronic effects are expected to shape its valence chemistry, probably making the +3 state important, but no atom has been chemically studied.
This element has not been synthesized or experimentally confirmed. All listed physicochemical properties are calculated, extrapolated, or model-dependent.
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Properties
Physical
N/A
Chemical
- Electron affinity
- Electron configuration
Thermodynamic
N/A
Nuclear
- Protons
- 121
- Known isotopes
- 0
- Stable isotopes
- 0
- Natural occurrence
- not_observed
Abundance
N/A
Safety
- Radioactive
- Yes
Crystal Structure
N/A
Electronic Structure
- Electrons per shell
- 2, 8, 18, 32, 33, 18, 8, 2
Identifiers
- CAS number
- 54899-56-8
Electron Configuration Predicted
——Electron configuration data not available for this ion.
Atomic model
Isotopes change neutron count, mass, and stability — not the electron configuration of a neutral atom.
N/A
Schematic atomic model, not to scale.
Atomic Fingerprint
Emission / Absorption Spectrum
Isotope Distribution
No stable isotopes.
| Mass number | Atomic mass (u) | Natural abundance | Half-life |
|---|
Phase / State
Phase/state data not available
N/A
Phase/state data not available