H−H+Br−Br→2H−Br 433+192=6252=728×364 Energy absorbed Energy released Net energy released =ΣHR−ΣHp =625−728=−103 kJ. Related Theory Fluorine has high bond energy because it is smallest among these molecules so it is tightly bonded to other atoms due to greater nuclear charge.
If the bond energies of H- H, Br- Br, and H- Br are 433,192 and 364 ~kJ / mol^-1 respectively, the Δ H° for the reaction H_2(g)+ Br_2(g) → 2 HBr_(g)…
NEET UG 2004 — Chemistry Physical Chemistry
2004mcqmedium
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:
Official previous-year question
Held on 30 Apr 2004 · Verified 9 Jul 2026.
Options
- A
−261 kJ
- B
+103 kJ
- C
+261 kJ
- D
−103 kJ
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