Source: https://guthlabs.ai/docs/instruments/le-chatelier-shift-predictor/implementation/

instrument implementation / implementation-contract

# Le Chatelier Shift Predictor implementation

A source-bound implementation contract for Le Chatelier Shift Predictor; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## 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**: t6-078

**Effect**: Computation or source lookup only

## Input and validation requirements

The input ΔH = 0 is numerically ordinary but lies outside the required positive/negative enthalpy classification. Without explicit validation, a rule engine could incorrectly choose a temperature-shift direction instead of rejecting or returning undefined.

## 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": {
    "reaction": "N2(g) + 3 H2(g) ⇌ 2 NH3(g)",
    "delta_H_sign": "negative",
    "stress": {
      "type": "concentration",
      "action": "add",
      "species": "H2",
      "amount": "positive"
    }
  },
  "expected_outputs": {
    "shift_direction": "right, toward NH3",
    "rationale": "Adding a reactant consumes the added H2; equilibrium shifts in the direction that removes H2.",
    "stoichiometric_check": "Left side contains H2; rightward reaction consumes 3 mol H2 per 2 mol NH3 formed."
  },
  "working": "1. Identify the stressed species: H2. 2. H2 is on the left side, so the forward/right reaction consumes it. 3. Therefore the predicted shift is right, producing more NH3. 4. Stoichiometric check: 1 forward extent consumes 3 H2 and forms 2 NH3; the direction is unambiguous."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/le-chatelier-shift-predictor/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/le-chatelier-shift-predictor/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/le-chatelier-shift-predictor/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-tranche6/tranche6-results.json`