From the Group 6A elements shown in the diagram, the element with the largest atomic radius is ___. In Period 3, the element with the largest atomic radius is ___. The three atoms which would form ions which are smaller in size than their parent atoms are Al, Mg, and ___. In Period 3,___ has the highest ionization energy, while in Group 6A ___ has the highest ionization energy. O; Ar; Na; Na; O

O; Ar; Cl; Na; Se

Se; Na; Na; Ar; O

Se; Na; Cl; Ar; Se