The bond dissociation energies of X₂, Y₂ and XY are in the ratio of 1:0.5:1. AH for the
formation of XY is - 200KJ mol⁻¹.the bond dissociation energy of X2 will be
(1) 200KJ mol⁻¹
(2) 100KJ mol⁻¹
(3) 800KJ mol⁻¹
(4) 400kJ mol⁻¹