Bond Enthalpy Reaction Estimator mechanism

Model scope

The arithmetic engine and stated approximation formula are acceptable. Review is required because the lookup table values, bond-type conventions, phase assumptions, and exact output unit are not specified sufficiently for deterministic production results. The honest-label warning is appropriate but should also state that average bond energies usually approximate gas-phase reaction enthalpies rather than exact ΔH°rxn values.

• The formula ΔH≈Σ(bonds broken)−Σ(bonds formed) is the standard average-bond-enthalpy estimate when all bond energies are positive dissociation energies and bond counts are stoichiometrically correct.
• The specification does not provide the actual bond-energy lookup values or define the table version, so results are not reproducible from the specification alone.
• The output is labeled ΔH°rxn, but average bond dissociation energies generally estimate gas-phase reaction enthalpies and do not directly provide exact standard enthalpies, especially when condensed phases are involved.
• The input contract should explicitly require nonnegative integer bond counts, valid bond-type keys, and complete accounting of every bond broken and formed.

Units and conventions

• All listed bond energies are positive average bond dissociation energies in kJ/mol of bonds.
• The reported result is kJ/mol of reaction as written, not kJ/mol of individual bonds.
• The reaction is treated as a gas-phase bond-counting estimate unless phase handling is explicitly added.
• Bond energies are assumed to come from one consistent lookup table and bond notation, such as C-H, C-C, C=C, O=O, O-H, H-H, Cl-Cl, and H-Cl.
• No conversion between kJ/mol and other energy units is performed unless explicitly implemented.

Inspectable vector

One of 4 source-bound review vectors:

{
  "inputs": {
    "reaction": "H2(g) + Cl2(g) -> 2 HCl(g)",
    "bonds_broken": [
      {
        "bond": "H-H",
        "count": 1,
        "energy_kJ_per_mol": 436
      },
      {
        "bond": "Cl-Cl",
        "count": 1,
        "energy_kJ_per_mol": 243
      }
    ],
    "bonds_formed": [
      {
        "bond": "H-Cl",
        "count": 2,
        "energy_kJ_per_mol": 431
      }
    ]
  },
  "expected_outputs": {
    "estimated_delta_H_kJ_per_mol_reaction": -183
  },
  "working": "Broken-bond sum = (1 × 436) + (1 × 243) = 436 + 243 = 679 kJ/mol. Formed-bond sum = 2 × 431 = 862 kJ/mol. ΔH ≈ 679 − 862 = −183 kJ/mol reaction."
}

Failure boundary

BREAK_CLAIMED · SELF_FLAGGED

The extreme finite-looking count produces Infinity for both bond-energy sums and then Infinity − Infinity = NaN; without finite and physical-input validation, the estimator returns an undefined result. The specification also has no actual formula branch, despite requiring branch-switch testing.

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche6/tranche6-results.json
• BOUNDARY_HAZARD_CATALOG.json