Question

Ce-58 is a member of

(A) s-block elements

(B) p-block elements

(C) d-block elements

(D) f-block

Answer 1

• Ce-58 is a member of f-block which can be predicted by its electronic configuration which is as follows:

${}_{58}{}^{140}\mathrm{Ce}$: $\left[\mathrm{Xe}\right]4f^{1}5d^{1}6s^2$

• As we can see in the electronic configuration the last electrons enter an f-block element which means this element belongs to the f-block element.
• Cerium is the first element of the lanthanide series and includes cerium, (Ce) total of 14 elements starting from cerium(58) up to Lutetium(Lu-71).
• Lanthanides are belongs to f-block elements but they are placed below the periodic table in a horizontal column.
• f-block elements are called inner transition elements because the last electron enters an f-shell which is the pre-pan ultimate shell of the element.