Using the bond energies (kJ/mol) H–H 436, Br–Br 193, H–Br 366, estimate the enthalpy change for H + Br → 2HBr.
Answer and explanation
Correct answer: C. -103 kJ
- Step 1: .
- Step 2: Substituting the bond energies gives kJ.
Answer
-103 kJ.
Why not the others: +103 kJ: the sign is reversed, which would make the reaction endothermic.
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