If the bond energies of H−H,Br−Br, and H−Br are 433,192 and 364 kJ/mol−1 respectively, the ΔH∘ for the reaction H2(g)+Br2(g)→2HBr(g) is:
Held on 30 Apr 2004 · Verified 9 Jul 2026.
−261 kJ
+103 kJ
+261 kJ
−103 kJ
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