Source: https://guthlabs.ai/docs/instruments/rate-law-reaction-order-determiner/
instrument / verified-clean
# Rate Law / Reaction-Order Determiner
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**: t6-114
**Ledger rows**: 1
No ledger note is attached.
## Review findings
The core log-ratio arithmetic is valid for isolated initial-rate comparisons, but the claimed multi-reactant functionality and rate-constant output are underspecified. Add a complete rate-law algorithm, constraints for which concentrations must remain fixed, an explicit k formula with unit propagation, and a policy for noisy or overdetermined data.
### Formula and scope findings
- The stated ratio formula, (rate2/rate1)=([A]2/[A]1)^m, correctly determines the order in A only when every other reactant concentration is identical between the two trials.
- The specification does not provide the corresponding equations for B, C, or additional reactants, so it cannot determine the order in each reactant as claimed.
- The specification does not state how to calculate the rate constant k from the determined orders; the required formula is k=rate/([A]^m[B]^n...).
- Overall order should be explicitly computed as the sum of individual reactant orders.
- Pairwise log-ratio calculations are insufficient when multiple concentrations change simultaneously; the instrument needs isolated comparisons or a stated multi-variable regression method.
### Unit assumptions
- Concentrations must use a declared and consistent unit within a calculation; standard kinetics notation commonly uses mol L^-1 (M).
- Initial rates must use a declared time unit, such as mol L^-1 s^-1.
- For rate law rate=k[A]^m[B]^n, k has units (concentration)^(1-overall order) time^-1.
- Log-ratio order calculations require positive concentrations and positive initial rates; logarithms of dimensional quantities are avoided by taking ratios with matching units.
- The unit-conversion vector assumes the reported concentrations are in mM and rates are in micromolar per second (uM/s).
## Boundary hardening
**BREAK_CLAIMED** · SELF_FLAGGED
The instrument has exposed invalid-input hazards at zero concentration and zero initial rate, where the logarithm formula is undefined or a ratio divides by zero. It also has a sign-convention hazard that can produce a negative rate constant if signed d[A]/dt values are treated as positive reaction rates.
## 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": {
"reactants": [
"A"
],
"trials": [
{
"A": "0.100 M",
"initial_rate": "0.00200 M/s"
},
{
"A": "0.200 M",
"initial_rate": "0.00800 M/s"
}
]
},
"expected_outputs": {
"order_A": 2,
"overall_order": 2,
"rate_constant": "0.200 M^-1 s^-1",
"rate_law": "rate = (0.200 M^-1 s^-1)[A]^2"
},
"working": "rate2/rate1 = 0.00800/0.00200 = 4.000. [A]2/[A]1 = 0.200/0.100 = 2.000. Therefore m = ln(4.000)/ln(2.000) = 2.00000. k = rate1/[A]1^2 = 0.00200/(0.100)^2 = 0.00200/0.0100 = 0.200 M^-1 s^-1. Overall order = 2."
}
````
## 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`