The superoxide ion, O₂⁻•, plays a key role in biological redox processes. The species contains an odd number of electrons and carries a –1 charge.
(a) Determine the total number of valence electrons that must be represented in a Lewis diagram for O₂⁻•.
(b) Draw one valid Lewis structure for O₂⁻• that includes the unpaired electron.
(c) Calculate the formal charge on each oxygen atom in the structure from part (b).
(d) Compare the O–O bond length you would expect for O₂⁻• with the bond lengths of neutral O₂ (dioxygen) and O₂²⁻ (peroxide). Justify your prediction using bond order arguments based on your Lewis structure.