Uranium
Uranium is a chemical element; it has symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom... Wikipedia
- Name, symbol: uranium, U
- Pronunciation: -nee-əm]]
- Appearance: silvery gray metallic, corrodes to a spalling black oxide coat in air
- Oxidation states: 6, 5, 4, 3, 2, 1 (a weakly basic oxide)
- Electronegativity: Pauling scale: 1.38
- energies: 1st: 597.6 kJ/mol, 2nd: 1420 kJ/mol
- Atomic radius: empirical: 156 pm
- Covalent radius: 196±7 pm
- Van der Waals radius: 186 pm
- Crystal structure: orthorhombic
- Speed of sound thin rod: 3155 m/s (at 20 °C)
- Thermal expansion: 13.9 µm/(m·K) (at 25 °C)
- Thermal conductivity: 27.5 W/(m·K)
- Electrical resistivity: 0.280 µΩ·m (at 0 °C)
- Magnetic ordering: paramagnetic
- Young's modulus: 208 GPa
- Shear modulus: 111 GPa
- Bulk modulus: 100 GPa
- Poisson ratio: 0.23
- Vickers hardness: 1960–2500 MPa
- Brinell hardness: 2350–3850 MPa
- CAS Number: 7440-61-1
- Naming: after planet Uranus, itself named after Greek god of the sky Uranus
- Discovery: Martin Heinrich Klaproth (1789)
- First isolation: Eugène-Melchior Péligot (1841)
- Data source: DuckDuckGo