eight valence electrons Click to see full answer. Similarly, how many valence electrons are in an atom?For neutral atoms, the number of valence electrons is equal to the atom’s main group number. The main group number for an element can be found from its column on the periodic table. For example, carbon is in group 4 and has 4 valence electrons. Oxygen is in group 6 and has 6 valence electrons.Similarly, which elements have the same number of valence electrons? Elements with the same number of valence electrons are found in the same column of the Periodic Table. All elements in the first column of the Periodic Table have 1 valence electron in an s orbital. These elements are known as Group 1A metals or alkali metals. Hereof, how many valence electrons do the elements in each group have? Following this rule: Elements in group 1 have one valence electron; elements in group 2 have two valence electrons; elements in group 13 have three valence electrons; elements in group 14 have four valence electrons; and so forth up to group 18.Which elements only need 2 valence electrons?The first electron shell can only hold two electrons.