Colligative Properties Suite 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

t4-183

Effect

Computation or source lookup only

Input and validation requirements

• Division-by-zero and invalid-input hazards can arise in upstream calculations of molarity, molality, or mole fractions if solvent mass, solution volume, or total mole amount is zero.
• Reject negative molality, molarity, temperature, Kb, Kf, or pressure values; enforce 0≤x_solvent≤1.
• Using Celsius directly in π=iMRT produces an incorrect result; temperature must be converted to kelvin.
• Mixing molality and molarity, or using Kb/Kf with incompatible units, produces dimensionally incorrect temperature changes.
• The van't Hoff factor is not always an integer and may vary with concentration, dissociation, association, or ion pairing; treating it as exact requires an explicit approximation.
• The dilute ideal-solution formulas may be inaccurate for concentrated electrolytes or nonideal solutions.
• P°_solvent is strongly temperature-dependent; the solvent vapor-pressure table must identify the temperature and pressure units.
• The current vapor-pressure formula does not directly return the claimed vapor-pressure lowering.

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": {
    "property": "boiling_point_elevation",
    "solvent": "water",
    "i": 2,
    "Kb": 0.512,
    "Kb_units": "K·kg·mol^-1",
    "m": 0.5,
    "m_units": "mol·kg^-1",
    "Tb_pure_C": 100
  },
  "expected_outputs": {
    "delta_Tb_K": 0.512,
    "new_boiling_point_C": 100.512
  },
  "working": "ΔTb=i·Kb·m=2.0×0.512×0.500=1.024×0.500=0.512 K. Tb,new=Tb°+ΔTb=100.000+0.512=100.512 °C."
}

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