Groups corresponding to the progressive filling of the `ns` and `np` orbitals represent the main group elements (also called representative elements). The total number of such groups in the periodic table is

Options

A. `8`
B. `7`
C. `6`
D. `5`

Answer

A

Explanation

Elements in groups `1` and `2` and `13` through `18`, i.e., `A`-group elements in the periodic table are called representative elements. Their last electron is assigned to an outermost `s-`or `p`-orbital. These elements show distinct and fairly regular variations in their properties with changes in atomic number. The discussion of these elements takes up the majority of space in the texts because it is these elements that cover the widest range of chemical and physical properties.