92238.03UUranium
Uranium (U) — element 92actinide · period 7
Uranium is a chemical element with the symbol U and atomic number 92. It is an actinide in period 7 of the periodic table (the f-block), with a standard atomic mass of 238.03 u. At room temperature (25 °C) uranium is a solid.
💡 Known for: The heaviest element found in large amounts in nature; it fuels nuclear power plants.
# Uranium properties
| Symbol | U |
|---|---|
| Atomic number | 92 |
| Atomic mass | 238.03 u |
| Category | actinide |
| Group | — (f-block, no group number) |
| Period | 7 |
| Block | f-block |
| Electron configuration | [Rn] 5f³ 6d¹ 7s² |
| Full configuration | 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f³ 6s² 6p⁶ 6d¹ 7s² |
| Electrons per shell | 2, 8, 18, 32, 21, 9, 2 |
| Protons / electrons | 92 / 92 |
| State at 25 °C | solid |
| Melting point | 1405.3 K (1132.2 °C, 2069.9 °F) |
| Boiling point | 4404 K (4130.9 °C, 7467.5 °F) |
| Density | 18.95 g/cm³ |
| Electronegativity (Pauling) | 1.38 |
| First ionization energy | 6.194 eV |
| Atomic radius | 175 pm |
| Discovered | 1789 |
# Electron configuration of uranium
The electron configuration of uranium is [Rn] 5f³ 6d¹ 7s², written out in full as 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f³ 6s² 6p⁶ 6d¹ 7s². Its 92 electrons fill 7 shells as 2, 8, 18, 32, 21, 9, 2, so the outermost shell holds 2 electrons.
# Related elements
PaProtactiniumprevious elementNpNeptuniumnext elementAcActiniumactinideThThoriumactinidePuPlutoniumactinideAmAmericiumactinideCmCuriumactinideBkBerkeliumactinideCfCaliforniumactinideEsEinsteiniumactinide
# Uranium FAQ
What is the atomic number of uranium?
The atomic number of uranium is 92: every uranium atom has 92 protons in its nucleus. Its symbol is U.
What is the atomic mass of uranium?
The standard atomic mass of uranium is 238.03 u.
What is the electron configuration of uranium?
Uranium's electron configuration is [Rn] 5f³ 6d¹ 7s² (1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f³ 6s² 6p⁶ 6d¹ 7s²), with 2, 8, 18, 32, 21, 9, 2 electrons per shell.
Is uranium a metal?
Yes. Uranium is an actinide, one of the metals.
What is the melting point of uranium?
Uranium melts at 1405.3 K (1132.2 °C, 2069.9 °F) and boils at 4404 K (4130.9 °C, 7467.5 °F).
What is uranium used for / known for?
The heaviest element found in large amounts in nature; it fuels nuclear power plants.