The bond dissociation enthalpy of the species in their correct order is:

Step-by-step solution

Bond order = 1 2 (N_b - N_a) . Higher bond order higher bond dissociation enthalpy. O₂^+ (15e): _ 1s ^2 _ 1s ^ *2 _ 2s ^2 _ 2s ^ *2 _ 2p_z ^2 _ 2p_x ^2 _ 2p_y ^2 _ 2p_x ^ *1 BO = 1 2 (10-5) = 2.5 O₂ (16e): _ 1s ^2 _ 1s ^ *2 _ 2s ^2 _ 2s ^ *2 _ 2p_z ^2 _ 2p_x ^2 _ 2p_y ^2 _ 2p_x ^ *1 _ 2p_y ^ *1 BO = 1 2 (10-6) = 2.0 O₂^- (17e): _ 1s ^2 _ 1s ^ *2 _ 2s ^2 _ 2s ^ *2 _ 2p_z ^2 _ 2p_x ^2 _ 2p_y ^2 _ 2p_x ^ *2 _ 2p_y ^ *1 BO = 1 2 (10-7) = 1.5 O₂²⁻ (18e): _ 1s ^2 _ 1s ^ *2 _ 2s ^2 _ 2s ^ *2 _ 2p_z ^2 _ 2p_x ^2 _ 2p_y ^2