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94Pu

Element 94

Plutonium

Actinides

Plutonium (Pu) is in the f-block of the periodic table — group 3, period 7.

Plutonium is a transuranic radioactive chemical element with symbol Pu and atomic number 94.

Key data

Atomic number
94
Atomic mass
244.000 u
Group / Period
3 / 7
Block
f-block
Phase at STP
Solid
Density
19.816 g/cm³
Melting point
639.4 °C
Boiling point
3231.8 °C
Electron configuration
[Rn] 5f6 7s2

Periodic table block

Plutonium is in the f-block (group 3, period 7). Elements land in the f-block when their highest-energy electrons fill an f subshell — these are the lanthanides and actinides shown beneath the main table.

s-blockp-blockd-blockf-block

New to this? Periodic table blocks explained: s, p, d, and f

Common uses

  • Nuclear weapons
  • Radioisotope batteries
  • Curiosity rover power

Discovery

Year: 1940

Discovered by: Glenn T. Seaborg

Frequently asked questions

What is the atomic number of Plutonium?

Plutonium has atomic number 94. Its symbol is Pu and its atomic mass is 244 u.

What category of element is Plutonium?

Plutonium is classified as actinides. It sits in group 3, period 7 of the periodic table.

What block of the periodic table is Plutonium in?

Plutonium is in the f-block (group 3, period 7). Its highest-energy electrons occupy the f subshell — you can see this in its electron configuration, [Rn] 5f6 7s2.

What is Plutonium used for?

Common uses of Plutonium include: Nuclear weapons, Radioisotope batteries, Curiosity rover power.

When was Plutonium discovered?

Plutonium was discovered in 1940 by Glenn T. Seaborg.

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