Question

lanthanides and actinoids start from which element in periodic table and tell the border elements

Answer 1

The lanthanides and the actinides make up the f block of the Periodic Table.

The lanthanides are the elements produced as the 4f sublevel is filled with electrons and the actinides are formed while filling the 5f sublevel.

Generally speaking, the lanthanides have electron configurations that follow the Aufbau rule.

For Further details,Please Refer to attachment :)

Lanthanides start from 57th element

actinoids start from 89th Element

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