Electronic Configurations and Types of Elements: S-, P-, D-, F- Blocks - The f-Block Elements (Inner-transition Elements)

Actinoid contraction is greater from element to element than the lanthanoid contraction, why?

Out of Lu(OH)₃ and La(OH)₃ which is more basic and why?

Compare lanthanoids and actinoids.

Justify the position of lanthanides and actinides in the periodic table.

The actinoid elements which show the highest oxidation state of +7 are ____________.

In the modern periodic table, elements are arranged in order of increasing atomic numbers which is related to the electronic configuration. Depending upon the type of orbitals receiving the last electron, the elements in the periodic table have been divided into four blocks, viz, s, p, d and f. The modern periodic table consists of 7 periods and 18 groups. Each period begins with the filling of a new energy shell. In accordance with the Arfbau principle, the seven periods have 2, 8, 8, 18, 18, 32 and 32 elements respectively. The seventh period is still incomplete. To avoid the periodic table being too long, the two series of f-block elements, called lanthanoids and actinoids are placed at the bottom of the main body of the periodic table.

The element with atomic number 57 belongs to ______.

What are actinoids? Give three examples.

Electronic configurations of four elements A, B, C and D are given below:

(A) 1s²2s²2p⁶

(B) 1s²2s²2p⁴

(C) 1s²2s²2p⁶3s¹

(D) 1s²2s²2p⁵

Which of the following is the correct order of increasing tendency to gain electron: