Element story

Plutonium

Atomic number 94 means that every Plutonium nucleus contains 94 protons. That proton count is the element's identity: change it and you no longer have Plutonium.

Start with the nucleus

Atomic number 94 means that every Plutonium nucleus contains 94 protons. That proton count is the element's identity: change it and you no longer have Plutonium.

Plutonium (Pu) is chemical element 94. It belongs to the actinoids, and its reference state at room temperature is a solid. Those basic facts are a useful starting point for its chemistry and applications.

In practice, it turns up most often in nuclear energy, space power systems and scientific research.

See the atom

Conceptual visual: electron shells are a learning aid, not a literal picture of quantum orbitals.

What this number means

Atomic number 94 means that every Plutonium nucleus contains 94 protons. That proton count is the element's identity: change it and you no longer have Plutonium.

Keep exploring

→ Plutonium · Atomic structure · Periodic trends

Sources

EN · institutional/academic · IUPAC · CIAAW · NIST