Element 92 · Uranium (U)

Uranium Bohr model: diagram and electrons per shell

The uranium Bohr model shows a uranium atom (U) as a small nucleus with its electrons circling it in 7 shells: 2 in shell K, 8 in shell L, 18 in shell M, 32 in shell N, 21 in shell O, 9 in shell P and 2 in shell Q. This page has a rotating 3D uranium Bohr model, a flat diagram, a table of the electrons in each shell and the steps to draw it yourself.

Rotate the uranium Bohr model in 3D

Drag to orbit, scroll to zoom.

This is a Bohr model of uranium (U), a simplified picture of a single uranium atom. Its nucleus holds 92 protons, and a neutral uranium atom has 92 electrons, arranged around it in 7 shells (2 in shell K, 8 in shell L, 18 in shell M, 32 in shell N, 21 in shell O, 9 in shell P and 2 in shell Q).

U K · 21s² L · 82s² 2p⁶ M · 183s² 3p⁶ 3d¹⁰ N · 324s² 4p⁶ 4d¹⁰ 4f¹⁴ O · 215s² 5p⁶ 5d¹⁰ 5f³ P · 96s² 6p⁶ 6d¹ Q · 27s²

Uranium Bohr model diagram

Bohr model diagram of uranium: a nucleus of 92 protons with 92 electrons on 7 shells, 2 in shell K, 8 in shell L, 18 in shell M, 32 in shell N, 21 in shell O, 9 in shell P and 2 in shell Q, each ring labelled with its shell letter. — The uranium Bohr model drawn flat: each ring is a shell, labelled with its letter, and every dot is an electron (2 in shell K, 8 in shell L, 18 in shell M, 32 in shell N, 21 in shell O, 9 in shell P and 2 in shell Q).

Uranium electrons per shell

A neutral uranium atom has 92 electrons, one for each of its 92 protons. They fill the shells from the nucleus outwards: 2 in shell K, 8 in shell L, 18 in shell M, 32 in shell N, 21 in shell O, 9 in shell P and 2 in shell Q.

Electrons in each shell of the uranium Bohr model
Shell	Shell number (n)	Electrons	Most it can hold (2n²)	Subshells
K	1	2	2	1s²
L	2	8	8	2s² 2p⁶
M	3	18	18	3s² 3p⁶ 3d¹⁰
N	4	32	32	4s² 4p⁶ 4d¹⁰ 4f¹⁴
O	5	21	50	5s² 5p⁶ 5d¹⁰ 5f³
P	6	9	72	6s² 6p⁶ 6d¹
Q	7	2	98	7s²

How the uranium Bohr model builds up, shell by shell

Watch the uranium Bohr model come together: the nucleus first, then each shell in turn, from the innermost outwards, with its electrons joining the ring. The legend names every shell and counts its electrons, so you can read off the arrangement (2 in shell K, 8 in shell L, 18 in shell M, 32 in shell N, 21 in shell O, 9 in shell P and 2 in shell Q) as it forms.

Animation of the uranium Bohr model being built: a nucleus of 92 protons appears first, then each shell grows in around it and takes its electrons, giving 92 electrons on 7 shells (2 in shell K, 8 in shell L, 18 in shell M, 32 in shell N, 21 in shell O, 9 in shell P and 2 in shell Q). — The uranium Bohr model built up in six seconds: the nucleus first, then each shell with its electrons, ending with 2 in shell K, 8 in shell L, 18 in shell M, 32 in shell N, 21 in shell O, 9 in shell P and 2 in shell Q. Protons are red, neutrons yellow and electrons blue.

How to draw the uranium Bohr model

Find the atomic number. Uranium has atomic number 92, so a neutral atom has 92 protons and 92 electrons.
Draw the nucleus. Put a circle in the centre and write U in it. The 92 protons sit there with the neutrons.
Draw the shells. Sketch 7 shells as rings around the nucleus. A shell holds at most 2n² electrons: 2 in the first, 8 in the second, 18 in the third and 32 in the fourth.
Place the electrons. Fill from the inside out: 2 in shell K, 8 in shell L, 18 in shell M, 32 in shell N, 21 in shell O, 9 in shell P and 2 in shell Q.
Check the total. 2 + 8 + 18 + 32 + 21 + 9 + 2 = 92, the atomic number, so every electron is accounted for.

Atomic data for the uranium Bohr model

The numbers behind the uranium Bohr model, grouped by topic. Radii are in picometres (pm) and energies in kilojoules per mole (kJ/mol).

Identity

Symbol: U
Atomic number: 92
Atomic mass: 238.0289 u
Family: Actinides
Position: period 7 of the f-block
Block: f-block

Electron configuration

Full: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f³ 6d¹
Shorthand: [Rn] 5f³ 6d¹ 7s²
Electrons per shell: 2, 8, 18, 32, 21, 9, 2
Outer-shell electrons: 2 in shell Q

Ionisation energies

I₁: 597.6
I₂: 1420

Energy to remove each electron in turn (kJ/mol). A sharp jump means the next electron comes from an inner shell.

Atomic radii

Empirical (pm): 175
Covalent (pm): 170
Van der Waals (pm): 186

Electronegativity and electron affinity

Electronegativity (Pauling): 1.38
Electron affinity (kJ/mol): 50.94

Oxidation states

Charges the element commonly takes in compounds.

Physical properties, abundance and history of uranium

Bulk properties of uranium, how common it is, who discovered it and some of its compounds.

Physical properties

Phase at room conditions: Solid
Melting point: 1132.15°C (1405.3 K)
Boiling point: 4130.85°C (4404 K)
Density: 19.1 g/cm³
Thermal conductivity (W/m·K): 27.5
Specific heat (J/g·K): 0.116
Molar heat capacity (J/mol·K): 27.665
Heat of fusion (kJ/mol): 12.6
Heat of vaporisation (kJ/mol): 417

Abundance

Earth's crust (mg/kg): 2.7
Oceans (mg/L): 0.003

Discovery

Discovered by: Martin Heinrich Klaproth
Year: 1789

Common compounds

Uranium U
Uranyl acetate C4H6O6U
Uranium hexafluoride F6U
Uranium trioxide O3U
Uranyl Nitrate N2O8U
Uraninite H4O2U
Uranyl fluoride F2O2U
Uranyl acetate dihydrate C4H12O8U

Compounds listed in the PubChem database.

Main isotopes of uranium

Isotopes of uranium share the same 92 protons but differ in neutrons. Natural isotopes come first, then the longest-lived others.

Main isotopes of uranium: mass number, abundance, half-life and decay
Mass number	Natural abundance	Half-life	Decay
232	–	68.9 y	α, 24Ne, SF, 28Mg
233	–	159.19 ky	α, SF, 24Ne, 28Mg
234	0.005 %	245.5 ky	α, SF, 28Mg, 26Ne
235	0.72 %	704 My	α, SF, 20Ne, 25Ne, 28Mg
236	–	23.42 My	α, SF
238	99.274 %	4.463 Gy	α, SF, 2β⁻

α = alpha decay, β⁻ = beta-minus, β⁺ = beta-plus, EC = electron capture, SF = spontaneous fission, p / n = proton / neutron emission.

More about uranium

Uranium on the periodic table – properties, isotopes, uses and the full uranium page.
Actinides – all actinide elements and their trends.
Bohr model of every element – the Bohr model of all 118 elements.