Source: https://guthlabs.ai/docs/instruments/ksp-solubility-calculator/
instrument / verified-clean
# Ksp Solubility Calculator
The current ledger marks this instrument verified clean within the source-bound verification corpus.
Status: **VERIFIED_CLEAN**Lifecycle: **verified-clean**
## Inspectable records
[01**Overview**Purpose and lifecycle]()[02**Mechanism**Method and assumptions]()[03**Implementation**Binding and validation]()[04**Qualification**Evidence and errata]()
## Ledger state
The current ledger marks this instrument verified clean within the source-bound verification corpus.
**Area**: Chemistry & Materials
**Tranche**: tranche-6
**Evidence ID**: t6-068
**Ledger rows**: 1
No ledger note is attached.
## Review findings
The four vectors are valid under the stated concentration-based, ideal-dilute assumptions. Implementation should add common-ion identity, molar mass or chemical formula, temperature/database metadata, validation of physical roots, and explicit activity-versus-concentration labeling.
### Formula and scope findings
- The core concentration-based relation Ksp=[A]^x[B]^y is standard for a salt dissolving as A_xB_y(s) ⇌ xA + yB, but the common-ion formula is underspecified: the instrument must identify whether the added ion is A or B and apply the corresponding stoichiometric substitution.
- The advertised g/L output requires a molar mass, but molar mass or chemical formula is absent from the listed inputs.
- The specification does not state whether Ksp values use concentrations or activities. The stated equation is valid as a concentration approximation for sufficiently dilute solutions, not universally as a thermodynamic activity expression.
- For higher stoichiometries, the physical nonnegative root must be selected; polynomial equations can have multiple mathematical roots. The inverse calculation from s to Ksp is not explicitly defined, although it follows from the stated equation.
### Unit assumptions
- Ksp is dimensionless or treated numerically in the conventional concentration-standard-state convention.
- All dissolved concentrations and common-ion concentrations are in mol/L (M); any mM input must be converted to M before calculation.
- The solid phase activity is 1, temperature is fixed, and activity-coefficient effects are neglected.
- g/L is calculated as s in mol/L multiplied by molar mass in g/mol.
- The listed molar masses are an additional required input when g/L is requested.
## Boundary hardening
**BREAK_CLAIMED** · SELF_FLAGGED
The negative-Ksp vector must be rejected because the real solubility formula has a negative square-root argument. The specification also leaves unit interpretation and the distinction between free-ion and total common-ion concentration insufficiently explicit, creating possible incorrect results if the interface accepts an unqualified numeric common-ion value.
## Errata and corrections
No applied erratum is attached to this unique-name record.
## Inspectable example
4 review vectors are recorded. One source-bound sample is shown below.
````
{
"inputs": {
"salt": "AgCl",
"x": 1,
"y": 1,
"Ksp": 1.8e-10,
"common_ion": null,
"molar_mass_g_per_mol": 143.321
},
"expected_outputs": {
"molar_solubility_s_M": 0.00001341640786,
"solubility_g_per_L": 0.001922852991
},
"working": "AgCl ⇌ Ag+ + Cl−, so [Ag+]=s and [Cl−]=s. Ksp=s^2. s=sqrt(1.8×10^−10)=sqrt(1.8)×10^−5=1.341640786×10^−5 M. g/L=s×M=1.341640786×10^−5×143.321=1.922852991×10^−3 g/L."
}
````
## Related workflows
No source-defined multi-instrument workflow membership is recorded.
## Sources and evidence
These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.
- `VERIFIED_LEDGER.json · VERIFIED_CLEAN`
- `evidence-tranche6/tranche6-results.json`
- `BOUNDARY_HAZARD_CATALOG.json`