Source: https://guthlabs.ai/docs/instruments/molarity-calculator/mechanism/

instrument mechanism / verified-clean

# Molarity Calculator mechanism

The inspectable method record for Molarity Calculator, kept separate from implementation and qualification.

Status: **VERIFIED_CLEAN**Lifecycle: **verified-clean**

## Model scope

NEEDS_REVIEW because the formula is standard but volume-unit handling, mass/molar-mass unit compatibility, formula-parser scope, atomic-weight-table selection, and behavior when both mass and moles are supplied are unspecified.

- C=n/V is the standard molarity formula only when V is the final solution volume expressed in liters.

- n=mass/M is correct only when mass and molar mass use compatible units, such as grams and grams per mole.

- The specification does not define how a supplied chemical formula is parsed, including hydrates, parentheses, charges, or atomic-weight precision/version.

- The specification does not define precedence or validation when both mass and moles are supplied.

## Units and conventions

- Molarity output is in mol/L.

- Volume must be converted to liters before applying C=n/V; 1 L = 1000 mL.

- If mass is supplied in grams, molar mass must be in g/mol.

- The volume means final solution volume, not the volume of solvent used.

- Formula-derived molar masses depend on the selected atomic-weights table and its precision.

## Inspectable vector

One of 4 source-bound review vectors:

````
{
  "inputs": {
    "mode": "mass",
    "mass_g": 5.844,
    "molar_mass_g_per_mol": 58.44,
    "solution_volume_L": 0.5
  },
  "expected_outputs": {
    "molarity_mol_per_L": 0.2
  },
  "working": "n = mass / M = 5.844 g / 58.44 g/mol = 0.100 mol. C = n / V = 0.100 mol / 0.500 L = 0.200 mol/L."
}
````

## Failure boundary

**BREAK_CLAIMED** · SELF_FLAGGED

A zero-volume input produces an undefined division and must be rejected. A volume supplied in milliliters also produces a factor-of-1000 error if the calculator assumes the numeric value is already in liters without explicit conversion.

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/molarity-calculator/>)[03**Implementation**](<https://guthlabs.ai/docs/instruments/molarity-calculator/implementation/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/molarity-calculator/qualification/>)

## Sources and evidence

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

- `VERIFIED_LEDGER.json`

- `evidence-tranche2/tranche2-results.json`

- `BOUNDARY_HAZARD_CATALOG.json`