Justify the position of lanthanides and actinides in the periodic table
Answers
Answer:
The reason why Lanthanides and Actinides are located at the bottom of the periodical table is because of their properties and in the block in which electrons fill up. The lanthanides include elements 58 to 71 (fill out the 4f subshell) and the actinides include elements 89 to 103 (fill out the 5f subshell).
Answer:
1. In sixth period after lanthanum, the electrons are preferentially filled in inner 4f sub shell and these 14 elements following lanthanum show similar chemical properties. Therefore these elements are grouped together and placed at the bottom of the periodic table. This position can be justified as follows. Lanthanoids have general electronic configuration [Xe] 4f2-14 5d0-1 6s2 The common oxidation state of lanthanoids is +3 All these elements have similar physical and chemical properties. 2. Similarly the fourteen elements following actinium resemble in their physical and chemical properties. 3. If we place these elements after Lanthanum in the periodic table below 4d series and actinides below 5d series, the properties of the elements belongs to a group would be different and it would affect the proper structure of the periodic table. 4. Hence a separate position is provided to the inner transition elements at the bottom of the periodic table.Read more on Sarthaks.com - https://www.sarthaks.com/874113/justify-the-position-of-lanthanides-and-actinides-in-the-periodic-table