f-block Elements are those in which the last electron enters the f-orbital of the anti-penultimate shell. Here, we will discuss about the f-block elements.
What are f-block
- These are elements in which last electron enters any one of the 7 orbitals of their respective penultimate shell.
- General outer electronic configuration : (n – 2) f 0-14 (n-1) d 0-2 ns 2 where n= 6 – 7
- There are 2 series of f-block elements each containing 14 elements.
- Therefore, there are 28 f-block elements in the periodic table.
- They are placed at the bottom of the periodic table.
- The elements of the first series 58Ce – 71 Lu. It forms the sixth period and are Lanthanides. These all the members follow La and resemble closely with La. 4f orbitals are filled here.
- The elements of the second series 90 Th – 103 Lr It forms the seventh period. These are actinoids. These all the members follow Ac and resemble closely with Ac. 5f orbitals are filled here.
- All the actinoids are radioactive elements.
- All the f-block elements are the inner transition elements.
- 11 elements are transuranic elements which follow Uranium.
General characteristics of f-block elements
- f-block are heavy metals.
- These elements have high melting point and boiling point.
- They show variable oxidation states in their compounds.
- These elements form the compounds which are generally coloured.
- They form complexes.
- Most of the actinides are radioactive.
- f-block elements show the reactivity of actinides and have magnetic properties.
- When the atomic number of the f-block increases, the atomic radii decreases. This is Lanthanoid and actinoid contraction.
- They are highly electropositive and highly reactive.
- f-block placed separately to conserve the space in the periodic table.
Check out the post on what is d-block elements here :
For more updates join me on
You Tube Channel :
Website :