How are the vertical columns on the periodic table referred to?

The vertical columns on the periodic table are referred to as groups. Each group contains elements that share similar chemical properties and have the same number of valence electrons. This similarity in electron configuration leads to comparable reactivity and behavior among the elements within the same group.

For example, the alkali metals, found in group one, are highly reactive and have one valence electron, while the noble gases in group eighteen are known for their lack of reactivity due to having a full valence shell. Understanding these groupings helps in predicting the characteristics and reactions of different elements, making it a fundamental aspect of studying chemistry.