Question

Why are the elements in the long form of periodic table called s-block, p-block, d-block or f-block elements?
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Answer 1

Answer:

• The long form of the periodic table is based on the modern periodic law.

• It is divided into four blocks (s, p, d, f) based on the subshell (s, p, d, f) into which the last/differentiating electron enters.

• If the electron enters the s-subshell, the element is in s-block and so it is called s-block element. Similarly, the corresponding elements in their respective blocks are therefore called p-block, d-block, f-block elements.