EVERYDAY SCIENCE

Detailed explanation-1: -The vertical columns on the periodic table are called groups or families because of their similar chemical behavior. All the members of a family of elements have the same number of valence electrons and similar chemical properties.

Detailed explanation-2: -The chemical families consist of elements that have the same valence electron configuration and tend to have similar chemistry. The alkali metals (group 1) have ns1 valence electron configurations and form M+ ions, while the alkaline earth metals (group 2) have ns2 valence electron configurations and form M2+ ions.

Detailed explanation-3: -Valency of an element determines its chemical reactivity. Therefore, for all elements belonging to a particular group in the periodic table, the number of electrons in the outermost shell, that is the valence electrons will be the same.

Detailed explanation-4: -The s-, p-, and d-block elements of the periodic table are arranged into 18 numbered columns, or groups. The elements in each group have the same number of valence electrons.

Detailed explanation-5: -Atoms which are present in the same group of the periodic table will have same number of valence electrons. Hence Cl, I of group 17, Na, Ca group 1 and C, Ge group 14 have same valence electrons.