The lanthanides and actinides in the modern periodic table
Lanthanides and actinides
Lanthanides and actinides are located below the modern periodic table , They consists of two rows , They are known as the f-block elements because they have valence electrons in the f-shell , Lanthanides elements can be found naturally on Earth , and only one element of them is radioactive .
The lanthanides are 14 elements with atomic number 58 ( Cerium , Ce ) to 71 ( Lutetium , Lu ) , the actinides are 14 elements with atomic numbers from 90 ( Thorium , Th ) to 103 ( Lawrencium , Lr ) .
The lanthanides and the actinides belong to the periods 6 and 7 , respectively and between groups 3 and 4 , and they are set off below the main portion of the table , All of the actinudes are radioactive and some of them are not found in the nature .
The lanthanides are an important group of elements , Most of lanthanides are formed when uranium and plutonium undergo nuclear reactions , The lanthanides are the elements produced as the 4f sub level is filled with electrons and the actinides are formed while filling the 5f sub level ,
The actinudes are the elements which found in the second period of the f-block , And these elements fill up the 5 f sublevel , The lanthanides are the rare earth elements found in the first period of the f- block , And these elements fill up the 4 f sublevel.
Uses of lanthanides and actinides
The oxides of the lanthanides and actinides are used in the glass industry for polishing and making colored glass for goggles and television screens .
Due to the paramagnetic and ferromagnetic nature of the lanthanides and actinides , they are used in the magnetic and electronic devices .
The mixed oxides of the lanthanides are used in petroleum cracking , and ceric sulphate is a well known as oxidizing agent which is used in the volumetric analysis .
Lanthanides and actinides do not find any use in their pure state , So they are used in the production of the alloys of steel to improve the strength and workability of the steel .