Question

How many blocks are there in the modern periodic table?

Answer 1

Modern Periodic table:

• The modern periodic table is an arrangement of all the elements known in accordance with their increasing atomic number and recurring chemical properties.
• It is a tabular display of 118 chemical elements which consists of horizontal rows called periods and vertical columns are called groups.

On the basis of electronic configurations, the elements in the modern periodic table have been divided into four blocks. These are s, p, d, and f-blocks.

• s-block elements: Those elements (except He) in which the last electron enters into the s-subshell of the outermost energy level are called s-block elements.
• p-block elements: Those elements (except He) in which the last electron enters into the p-subshell of the outermost energy level are called p-block elements.
• d-block elements: Those elements in which the last electron enters the d-subshell of the outermost energy level are called d-block elements.
• f-block elements: Those elements in which the last electron enters into the f-subshell of the outermost energy level are called f-block elements.