Actinide series

Actinide series refers to the 15 metallic chemical elements found in period 7 of the periodic table. The series is named after the first element in the series, actinium. The actinide series includes elements with atomic numbers 89 (actinium) to 103 (lawrencium).

Characteristics

The actinide series is characterized by the filling of the 5f electron shell, similar to the lanthanide series which is characterized by the filling of the 4f shell. Actinides are typically heavy, dense metals with high melting points and boiling points.

Actinides are known for their strong radioactivity. All isotopes of actinides are radioactive, and many are very unstable and decay quickly. This radioactivity is due to the instability of the large atomic nuclei.

Elements in the Actinide Series

The actinide series includes the following elements:

• Actinium (Ac)
• Thorium (Th)
• Protactinium (Pa)
• Uranium (U)
• Neptunium (Np)
• Plutonium (Pu)
• Americium (Am)
• Curium (Cm)
• Berkelium (Bk)
• Californium (Cf)
• Einsteinium (Es)
• Fermium (Fm)
• Mendelevium (Md)
• Nobelium (No)
• Lawrencium (Lr)

Uses

Despite their radioactivity, actinides have several important uses. Uranium and plutonium are used as fuel in nuclear reactors and in the production of nuclear weapons. Other actinides, such as americium, are used in smoke detectors.

See Also

• Periodic table
• Lanthanide series
• Transition metals
• Radioactivity