If we talk about elements of group 6a , they have 6 electrons in the outermost shell as the group number indicates. There are 6 elements in group 6a including oxygen (O), sulfur (S), and selenium (Se), the metalloid tellurium (Te), and the metal polonium (Po).
The general electronic configuration of its all elements is ns^2, np^4 . They need only two electrons to complete their octet therefore, many exist as anions. Their generic Lewis dot is mentioned in the figure and here X indicates group 6a elements.
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