Oxygen, sulphur, selenium, tellurium, polonium and livermorium constitute Group 16 of the periodic table. This is sometimes known as group of chalcogens. The name is derived from the Greek word for brass and points to the association of sulphur and its congeners with copper. Most copper minerals contain either oxygen or sulphur and frequently the other members of the group.

The elements of Group16 have six electrons in the outermost shell and have ns²np⁴ general electronic configuration.

Due to increase in the number of shells, atomic and ionic radii increase from top to bottom in the group. The size of oxygen atom is, however, exceptionally small.

Which group 16 element is the most electronegative?

Oxygen

The elements of group 16 have higher values of electronegativity than the corresponding elements of group 15. Actually, oxygen is the second most electronegative element (EN=3.5), the first being fluorine (EN=4.0).