Source: https://guthlabs.ai/docs/instruments/calorimetry-calculator-q-mc-t/
instrument / verified-clean
# Calorimetry Calculator (q=mcΔT)
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-4
**Evidence ID**: t4-231
**Ledger rows**: 1
No ledger note is attached.
## Review findings
The core calorimetry relationships are standard, but the specification needs the exact ambiguity resolved: whether final temperature is supported through T_f=T_i+q/(mc), whether coffee-cup calorimeter heat capacity is assumed negligible, and whether C_cal is the total effective bomb-calorimeter constant. It must also define input units, positive/negative q conventions, validation constraints, and the specific-heat table value used for each selected material.
### Formula and scope findings
- q=mcΔT is correct for sensible heating or cooling when specific heat is treated as constant; it does not cover phase changes or temperature-dependent specific heat.
- The claimed final-temperature calculation has no explicit formula; it requires T_f=T_i+q/(mc), with a clearly defined sign convention.
- q_rxn=-q_solution is correct only when the coffee-cup calorimeter heat capacity is negligible; otherwise q_rxn=-(q_solution+q_cal).
- q_rxn=-C_cal·ΔT is correct when C_cal is the total effective bomb-calorimeter heat capacity and ΔT is the calorimeter temperature change; the specification does not define whether C_cal includes the vessel, water, and accessories.
- The specific-heat calculation c=q/(mΔT) requires ΔT to be nonzero and requires q to refer to the same material represented by m and ΔT.
### Unit assumptions
- Mass and specific heat must use compatible units, such as grams with J/(g·°C) or kilograms with J/(kg·K).
- A temperature difference in °C and the same numerical difference in K are interchangeable; absolute temperatures must use an explicit scale.
- If m is in grams and c is in J/(g·°C), q is in joules; divide by 1000 to report kilojoules.
- C_cal must be in J/°C or kJ/°C, matching the desired energy output.
- Material-selection mode requires a defined specific-heat table value, temperature range, phase, and provenance; the cited CRC table alone does not specify which value is used.
## Boundary hardening
**BREAK_CLAIMED** · SELF_FLAGGED
The zero-mass solve-for-specific-heat case produces a zero denominator and must be rejected as undefined. The cooling example also exposes a sign-convention hazard that can reverse both solution and reaction heat if ΔT is treated as a magnitude instead of T_final - T_initial.
## 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": {
"operation": "coffee_cup_heat_and_reaction_heat",
"mass_g": 250,
"specific_heat_J_per_g_C": 4.184,
"delta_T_C": 5
},
"expected_outputs": {
"q_solution_J": 5230,
"q_solution_kJ": 5.23,
"q_rxn_J": -5230,
"q_rxn_kJ": -5.23
},
"working": "q_solution = m·c·ΔT = 250.0 g × 4.184 J/(g·°C) × 5.0 °C = 1046 J/°C × 5.0 °C = 5230 J = 5.23 kJ. Assuming negligible calorimeter heat capacity, q_rxn = -q_solution = -5230 J = -5.23 kJ."
}
````
## 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-tranche4/tranche4-results.json`
- `BOUNDARY_HAZARD_CATALOG.json`