XY⟶X(g)+Y(g);ΔH=+akJ/mole…………..(i)X2⟶2X;ΔH=+akJ/mole…………… (ii) Y2⟶2Y;ΔH=+0.5akJ/mole…………. (iii) 21× (ii) +21× (iii) − (i), Gives 21X2+21Y2⟶XY;ΔH=(+2a+20.5a−a)kJ/mole+2a+20.5a−a=−200a=800.
If the bond dissociation energies of XY,X2 and Y2 (all diatomic molecules) are in the ratio of 1:1:0.5 and ΔtH for the formation of XY is −200 kJ mole−1. The bond dissociation energy of X2 will be
Held on 30 Apr 2005 · Verified 6 Jul 2026.
100 kJ mol−1
200 kJ mol−1
300 kJ mol−1
None of these
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