Standard Entropy of Reaction Calculator implementation

Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

Record owner

Guth Instruments

Lifecycle

verified-clean

Evidence ID

t4-254

Effect

Computation or source lookup only

Input and validation requirements

The extreme-magnitude vector produces Infinity in IEEE-754 JavaScript arithmetic because the product entropy sum overflows; the calculator should reject non-finite inputs or outputs. The specification also contains no genuine multi-regime formula branch, so the branch test is necessarily a zero-crossing probe.

Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

{
  "inputs": {
    "balanced_equation": "CH4(g) + 2 O2(g) -> CO2(g) + 2 H2O(l)",
    "S_standard": {
      "CH4(g)": 186.3,
      "O2(g)": 205,
      "CO2(g)": 213.7,
      "H2O(l)": 69.9
    },
    "S_unit": "J mol^-1 K^-1",
    "temperature_K": 298.15
  },
  "expected_outputs": {
    "delta_S_rxn": -242.8,
    "unit": "J mol^-1 K^-1"
  },
  "working": "Products = (1 × 213.7) + (2 × 69.9) = 213.7 + 139.8 = 353.5 J mol^-1 K^-1. Reactants = (1 × 186.3) + (2 × 205.0) = 186.3 + 410.0 = 596.3 J mol^-1 K^-1. ΔS°rxn = 353.5 − 596.3 = −242.8 J mol^-1 K^-1."
}

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-tranche4/tranche4-results.json