Ununseptium was discovered by a group of scientists from Russia and USA in 2009-2010.
Name: Ununseptium
Symbol: Uus
Atomic number: 117
Atomic weight: 294
State: presumably a solid
Group, period, block: 17, 7, p
Color: unknown
Classification: unknown
Electron configuration: 5f14 6d10 7s2 7p5
2,8,18,32,32,18,7
Physical properties
Density: no data
Melting point: 573€“773 K,300€“500 °C,572€“932 (predicted) °F
Boiling point: 823 K,550 °C,1022 (predicted) °F
Atomic properties
Oxidation states: -1, +1, +3, +5
Electronegativity: no data
Ionization energies: 1st: 742.9 kJ·mol-1
Covalent radius: 165 pm
Van der Waals radius: no data
- Uus
Electron Configuration
Isotopes
Ununseptium is an artificial element, and thus a standard atomic mass cannot be given. Like all artificial elements, it has no stable isotopes. The synthesized isotopes in 2009 were 293Uus and 294Uus. The longer-lived isotope is 294Uus with a half-life of 78 ms.