✔ 最佳答案
Refer to:
https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Chemical_Bonding/Fundamentals_of_Chemical_Bonding/Bond_Energies
Bond energies in Table 1:
E(N-H) = 391 kJ/mol
E(H-H) = 432 kJ/mol
E(N≡N) = 941 kJ/mol
(Bond energies from different sources may be slightly different.)
_ H
_ |
_ 2 H-N-H → 3 H-H + N≡N ΔH
Energy absorbed in bond breaking = 2 × 3 E(N-H) = 6 × 391 = 2346 kJ
Energy released in bond formation = 3 E(H-H) + E(N≡N) = 3(432) + (941) = 2237 kJ
ΔH = (2346 - 2237) kJ = +109 kJ