Chemical element · Atomic number 94

Plutonium

Plutonium in the periodic table: atomic number 94, electron configuration, atomic mass, physical data, oxidation states, media credit and visible sources.

Pu

Actinide

solid

[244.06420] u

A heavily oxidised piece of plutonium metal with a dull, mottled surfaceDocumented element sample

Plutonium metal with a heavy oxide layer; this is how samples of the reactive metal usually look.

Image credit: Beachheadbenjamin

Auto-oriented, limited to 1600 × 1200 pixels and re-encoded as WebP; the subject was not altered.

Commons fileLicence: CC BY-SA 4.0

Atomic classification

Plutonium in the Bohr shell modelThis shows the electron distribution of the neutral atom in a simplified shell model.: 2 · 8 · 18 · 32 · 24 · 8 · 2

Shell occupancy

Plutonium in the Bohr shell model

This shows the electron distribution of the neutral atom in a simplified shell model.

K · n=1
2 electrons
L · n=2
8 electrons
M · n=3
18 electrons
N · n=4
32 electrons
O · n=5
24 electrons
P · n=6
8 electrons
Q · n=7
2 electrons
Shell occupancy is derived from the versioned PubChem electron configuration. Dot angles are schematic and do not represent orbitals.
Electron configuration
[Rn]7s2 5f6
Electrons per shell
2 · 8 · 18 · 32 · 24 · 8 · 2
Group
not reported
Period
7
Block
F
Element category
Actinide

Physical and chemical properties

Atomic mass
[244.06420] u
Standard state
solid
Density
19.84 g/cm³
Melting point
913 K
Boiling point
3,501 K
Electronegativity
1.28 (Pauling)
First ionisation energy
6.06 eV
Oxidation states
+6, +5, +4, +3
Discovery
1940

Safety and periodic classification

Safety

Safe handling cannot be inferred from Plutonium's position in the periodic table alone. Laboratory, classroom and disposal decisions must follow the documentation for the exact material and its safety data sheet.

Position and comparison

Plutonium is in period 7 and the F block. Its direct neighbours by atomic number are Neptunium and Americium. The recorded Pauling electronegativity is 1.28. Periodic trends are compared only through the separately sourced neighbouring values.

Sources and scope

PubChem attributes element data to sources including IUPAC, NIST and IAEA. Quanta stores the referenced snapshot locally and leaves unknown values unavailable.

Where Plutonium sits among the 118 elements

The table compares the reported values for Plutonium with every other element that carries the same value in the snapshot. A rank is not a judgement, it is orientation: it says how unusual this value is across the periodic table.

ValuePlutoniumPosition in the data set
Melting point913 KRank 68 of 103 elements with a reported value. Highest: Carbon.
Boiling point3,501 KRank 29 of 93 elements with a reported value. Highest: Rhenium.
Density19.84 g/cm³Rank 6 of 96 elements with a reported value. Highest: Osmium.
Electronegativity (Pauling)1.28Rank 72 of 95 elements with a reported value. Highest: Fluorine.
Ionisation energy6.06 eVRank 75 of 102 elements with a reported value. Highest: Helium.

All values and ranks come from the PubChem Periodic Table snapshot, retrieved on 2026-07-15. Elements without a reported value are excluded, so the population differs per row.

The neighbours of Plutonium in the periodic table

Place in the table
No group number, period 7, F block. Classified as actinide, solid at standard conditions.
Direct neighbours
Atomic number 94. Preceded by Neptunium, followed by Americium.
Discovery
Recorded in the snapshot as: 1940. Who, where and under what circumstances is not part of that record, so this page carries the sourced year and no discovery narrative.
Oxidation states
+6, +5, +4, +3. They follow from the electron configuration [Rn]7s2 5f6 and indicate which compounds to expect.

Go from looking up chemistry to remembering it.

Turn your notes into source-backed study cards and review them at the right time.

Start for free

Starter stays free · no payment details