To find the valence electrons in an atom, identify what group the element is in. An element in group 1A has 1 valence electron. For example, Li is in group 1A, so that means it has one valence electron. If the element is in group 2A, then it has two valence electrons.
Valence electrons are the electrons in the outermost shell. A valence electron refers to an electron that is associated with an atom and that can take part in the formation of a chemical bond. In the case of a single covalent bond, both atoms in the bond give one valence electron in forming a shared pair. The presence of valence electrons can influence the element’s chemical characteristics and its ability to bond with other elements.
Columns in the periodic table represent groups or families of elements. They are related because of the similarities in the number of electrons in the outer shell, which is where valence electrons are located. These groups get their names in two ways: by the group number or by the element at the top of the column, with the exception of the lithium group. The columns are numbered from one to 18. However, columns three to 12 consist of transition metals, and their way of determining the valence electrons differ from other elements.