Home Developers Capabilities Weak-acid ICE

CVP verified calculation capability

Weak-acid ICE Calculation Capability

Monoprotic weak-acid ICE: HA ⇌ H+ + A− from formal C and Ka or pKa. Charge and mass balance; optional water at 25 °C. Reuses math.numerical.root. Not Henderson–Hasselbalch and not pH=−log10[H+] identities.

Chemistry · Equilibrium Capability ID chemistry.equilibrium.weak_acid version 1.0.4 CVP VERIFIED STALE Engineering

Model

ICE with water

Modes: ice · ice no water

Inputs / Outputs

Canonical symbols for this capability. Agent schemas remain the contract.

SymbolQuantityUnitRole
CFormal HA concentration in mol/L—input / output
pKapKa = −log10—input / output
KaAcid dissociation constant—input / output
pH——output
h——output
HA——output
A——output
oh——output
fraction_dissociated——output
Kw——output
pKw——output
T—°Coutput
model——output
include_water——output
solver——output

Assumptions / Validity

Declared scope for this capability. Do not use it outside this domain.

Assumptions

Not supported

Example

One numerical check. The calculator page holds worked steps and FAQ.

C=0.1 Ka=1.8e-5 mode=ice_no_water → x=(−Ka+√(Ka²+4 Ka C))/2

Open this example in the calculator

Trust

CVP VERIFIED · production STALE · CVP protocol 1.0.0-proposed · Engineering assurance · Monoprotic weak-acid ICE, + O3 mpmath tabulated [H+].. Computational verification is defined by CVP. Supplemental domain review (internal) and named expert review are defined by the Review policy and do not by themselves determine CVP conformance.

CVP
CVP VERIFIED · production STALE · CVP protocol 1.0.0-proposed · Engineering assurance · Monoprotic weak-acid ICE, + O3 mpmath tabulated [H+].· View Manifest · CVP overview · Specification
Verified scope
Monoprotic weak-acid ICE, + O3 mpmath tabulated [H+].
Assurance
Engineering
Declared partition coverage
PASS · 7/7 declared partitions (alias, pka, awkward, dilute, no-water, water, invalid-domain)
Deferred
Not a buffer and not a weak base.
Calculation version
1.0.4
Verification
13/13 calculation tests · 2/2 legacy golden · 6/6 legacy boundary · 5/5 legacy property
Production surface contract
6/6
Versions
Calculation 1.0.4 · CVP protocol 1.0.0-proposed · Evidence 2026-10-06.polynomial-value-underflow
Verification revision
2026-10-06.polynomial-value-underflow · 1/1 property · digest daaf072a9df9
Reference
O1 model · O3 expected_values · O3 numerical_behavior · O2 expected_values · O2 numerical_behavior
Numerical scope
O2: monoprotic weak-acid ICE vs a separate-module quadratic or Newton cubic (≤2 ULP). Not a buffer. Absolute 1e-8 vs O3 applies only to the published tabulated weak-acid vectors. Not a buffer.
Interfaces
PASS · UI (SSR) / REST / MCP
ui-ssr is query-result HTML, not a live browser session. Error-path engine·REST·MCP 1/1 (status, code, calculation_version). SSR compared on URL-canonical requested calculations; empty query is idle (not an error) and JSON-typed object/array inputs are REST/MCP-only.
CVP suite
3/3 golden · 5/5 CVP boundary · 7/7 invalid · 1/1 property · 1/1 metamorphic · 8/8 O3 · 2/2 cross-interface · 6/6 CVP contract
Supplemental domain review
Not performed
Named expert review
Not performed
Version lock
Supported (409 VERSION_MISMATCH)
Artifact consistency
Build verified · 1.0.4 (workspace artifacts agree)
Review-policy tier
Engine tested — catalog token engine_tested; supplemental; not CVP status
STALE · Build schema 1.0.4 matches page · production binding STALE · Semantic contract ✓ · Last attestation PASS · current evidence changed · re-attestation required · CVP STALE · attestation STALE — Production CURRENT withheld · Public/cache ✓ · Origin ✓

Call this capability

Human page, REST, and MCP share the same engine and calculation_version. Build verified hashes workspace artifacts only. After deploy, attest:production GETs canonical URLs twice — the public/cached view an Agent actually hits, and origin — including every /capabilities/{id} HTML page. Public Capability HTML version must match catalog before production attestation passes. Live Trust rows above fetch /.well-known/calculatorx-production-attestation.json and the output schema const. Build hashes: release integrity. That proves currently published page / engine / schema / evidence / MCP agree — not that a historical version is independently immutable. Reference Calculation Standard — Production surface contract 6/6.

curl -sS -X POST 'https://www.calculatorx.com/api/v1/calc/weak-acid-equilibrium' \
  -H 'Content-Type: application/json' \
  -d '{"inputs":{"C":0.1,"Ka":0.000018,"mode":"ice_no_water"},"calculation_version":"1.0.4"}'

POST /api/v1/calc/weak-acid-equilibrium. This is a POST calculate endpoint — do not GET it.

Full REST contract: REST API docs.

Tool id
weak-acid-equilibrium
Engine
weak-acid-equilibrium
REST
POST /api/v1/calc/weak-acid-equilibrium
MCP
execute_calculation with capability_id: "chemistry.equilibrium.weak_acid"
Agent input schema
Canonical (MCP / Agent)
Output schema
JSON Schema (latest)
Versioned input schema
Immutable pin (1.0.4)
Versioned output schema
Immutable pin (1.0.4)

References

Human-readable sources plus CVP reference evidence classes.

Sources

Reference evidence classes: O1 model · O3 expected_values · O3 numerical_behavior · O2 expected_values · O2 numerical_behavior

Try with an agent

Inspect, then execute. Same engine as REST and the human calculator.

curl -sS -X POST 'https://www.calculatorx.com/mcp' \
  -H 'Content-Type: application/json' \
  -H 'MCP-Protocol-Version: 2026-07-28' \
  -H 'Mcp-Method: tools/call' \
  -H 'Mcp-Name: inspect_capability' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"inspect_capability","arguments":{"capability_id":"chemistry.equilibrium.weak_acid"},"_meta":{"io.modelcontextprotocol/protocolVersion":"2026-07-28","io.modelcontextprotocol/clientInfo":{"name":"calculatorx-docs-example","version":"1.0.0"},"io.modelcontextprotocol/clientCapabilities":{}}}}'

Pin calculation_version (1.0.4) when the result must stay reproducible.

Inspect the trust tier and required assurance level before execution. Full protocol notes: MCP docs.