Question

disscuss the filling of 4f subshell in lanthanides series?​

Answer 1

Answer:

Lanthanides have the general electron configuration of the type (Xe)4f n 6s2. They're called 4f elements as they have incompletely filled 4f subshells. ... Removal of three electrons is easier from the 4f subshells, so they have a stable oxidation state of +3.

Explanation:

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Answer 2

Answer:

The lanthanide elements typically have ground state electron configurations of the (Xe)$4$f  n $6$s$2$ type.

Explanation:

Filling of 4f subshell in lanthanides series:

• lanthanum is not included in this generalization, it is listed in the table due to other similarities and its uniform trivalency. Three lanthanides exhibit deviations from the typical $4$f n $5$d0 $6$s$2$ pattern.
• When compared to $4$f$1$ $5$d$1$, Cerium's increase in effective nuclear charge following Lanthanum is insufficient to stabilize the $4$f$2$ $5$d0 configuration. The $4$f orbitals' energy cannot be contracted to levels well below the $5$d by the nuclear charge.
• The f$7$d1 configuration of gadolinium is in line with what we would anticipate from a stabilized half-filled f shell.

• Additionally, lutetium has the f$1$ $4$d$1$ configuration, in which the final electron is added in excess of what the $4$f shell can accommodate.

Note: The table you're looking at on provides the Lanthanides' ground state electron configurations.