Have each group member select a different element from this list:

B, C, N, O, and F. Have all group members look up the following values for their elements: valence electron configuration, covalent atomic radius, effective nuclear charge, first ionization energy, and Pauling electronegativity. All members should compare the values for their elements with those of the group. Repeat with O, S, Se, Te, and Po. Account for the trends you see by referring to quantum-mechanical shells. Note and provide a tentative explanation for any exceptions to trends you observe.