Lanthanides and Actinides
Lanthanides and Actinides are two prominent families of the periodic table of elements. Discussed below are the differences between the elements in these two families, and their common properties.
Why are the Lanthanide and Actinide Series Separated from the Periodic Table
Lanthanide and actinide are separated from the main body of the periodic table because of how electrons get filled up. They belong to the category of f-bock elements in which the f shell is progressively filled as electrons are added to the atoms. The properties of these elements differ from d-block and s-block. Another reason for placing them below the main body is that they fill up too much space and for simplicity of printing on a standard letter size paper.
Differences and Similarities between Lanthanides and Actinides |
|
What are the Differences |
|
Lanthanides | Actinides |
Rare-earth elements | Not rare-earth elements |
Reasonably abundant in the surface of the earth | Synthesized in the laboratory (except uranium, thorium) |
4f shell filled progressively | 5f shell filled progressively. |
Non-radioactive (except promethium) | Radioactive |
Do not form oxocations | Form oxocation |
Form compounds that are low in basicity | Form compounds that are high in basicity |
Have a low tendency to form complexes with ligands | Have a high tendency to form complexes with ligands |
Colorless | Most ions are colored |
Display maximum oxidation state of +4 | Display maximum oxidation states of +6 |
What Do They Have in Common |
|
Belong to the family of inner transitional metals | |
Have their f shell filled progressively by electrons | |
Have a common oxidation state of +3 | |
Show contraction in their atomic radii | |
Highly electropositive and highly reactive |
Why Actinides Have Greater Tendency to form Complexes than Lanthanides
Actinides have a greater tendency to form complexes than lanthanides because their ions are smaller and have a large concentration of charges. Therefore, actinides have high nuclear density than lanthanides. Besides, the 4f orbitals in the Ln3+ ion do not participate directly in bonding since the 5s2 and 5p6 orbitals shield it entirely.
References:
- Thoughtco.com
- Medium.com
- Shaivikchemistryclasses.com
- Tutorsonnet.com
- Differencebetween.net
- Askiitians.com