In the second f transition series, also known as the actinoid series, the filling up of 5f orbitals begins with thorium (Z = 90) and ends up with lawrencium (Z = 103).
Properties of actinide series
The actinides are the elements at the bottom of these two rows, while the top row is the lanthanide series. There are 15 actinide elements. The electronic configuration of the actinides utilizes the f sublevel, except lawrencium, a d-block element. The only two actinides found in appreciable quantities in the Earth’s crust are thorium and uranium.
- All are radioactive. These elements have no stable isotopes.
- Actinides are highly electropositive.
- Actinides are very dense metals with distinctive structures. As a result, numerous allotropes can be formed—plutonium has at least six allotropes.
- All the actinides are paramagnetic.
- Actinides display several valence states, typically more than the lanthanides.
- Actinium is used in scientific and medical research as a neutron source, indicator, and gamma source.
- Give Any Two Difference Between Lanthanoids And Actinoids
- Which Of The Following Belongs To The Actinoids Series Of Elements I La Ii Lu Iii U Iv Sm