# Calorimetry Lab Report Marking Guide

## Task

Students conduct a calorimetry investigation and write a lab report that determines the molar enthalpy of a reaction from their data.

## Curriculum alignment

This task assesses the following outcomes from Chemistry 30, Unit A: Thermochemical Changes.

- 30-A1.1k: recall the application of Q = mcΔt to the analysis of heat transfer ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23634))
- 30-A1.2s: perform calorimetry experiments to determine the molar enthalpy change of chemical reactions, using thermometers or temperature probes appropriately ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23647))
- 30-A1.3k: define enthalpy and molar enthalpy for chemical reactions ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23636))
- 30-A1.8k: use calorimetry data to determine the enthalpy changes in chemical reactions ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23641))
- 30-A1.5k: use and interpret ΔH notation to communicate and calculate energy changes in chemical reactions ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23638))
- 30-A1.4s: use appropriate SI units, fundamental and derived units, and significant digits, and use appropriate numeric, symbolic, graphical and linguistic modes of representation to communicate results ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23649))
- 30-A1.3s: analyze data and apply mathematical and conceptual models to develop and assess possible solutions ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23648))

## Rubric

| Criterion | Beginning | Developing | Proficient | Exemplary |
|---|---|---|---|---|
| Experimental procedure and data collection ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23647)) | Records temperature readings inconsistently; procedure steps missing or out of order. | Records temperature data with some gaps; procedure described but lacks detail on technique. | Records temperature data accurately using thermometer or probe correctly; procedure clearly described. | Records precise, consistent temperature data; procedure justifies technique choices and controls for heat loss. |
| Calculation of heat transfer and molar enthalpy ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23634), [Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23641), [Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23636)) | Applies Q = mcΔt incorrectly; molar enthalpy not calculated or calculated with major errors. | Applies Q = mcΔt with minor errors; molar enthalpy calculated but mass-to-mole conversion is flawed. | Applies Q = mcΔt correctly; calculates molar enthalpy accurately from calorimetry data. | Applies Q = mcΔt and molar enthalpy calculations correctly, showing all steps and correct unit conversions throughout. |
| Communication: units, significant digits, and ΔH notation ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23649), [Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23638)) | Omits units or significant digits; ΔH notation missing or used incorrectly. | Uses units and significant digits inconsistently; ΔH notation present but applied with errors. | Uses correct SI units and significant digits; applies ΔH notation correctly to represent energy change. | Uses correct units, significant digits, and ΔH notation throughout, with clear tables and graphs supporting the data. |
| Analysis and interpretation of results ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23648), [Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23641)) | Provides no discussion of accuracy or sources of error; conclusion unsupported by data. | Identifies one source of error without explaining its effect on results. | Identifies sources of error and explains their effect on the calculated molar enthalpy. | Evaluates sources of error, compares result to an accepted value, and explains discrepancies with reference to experimental limitations. |

## Scoring

Assign each of the four criteria a level: Beginning (1 point), Developing (2 points), Proficient (3 points), or Exemplary (4 points). Add the four scores for a total out of 16.

- 4 to 7: Beginning
- 8 to 10: Developing
- 11 to 13: Proficient
- 14 to 16: Exemplary

Report the overall level to the student along with the total score, so the score and the descriptive level match.

## Notes for the teacher

- Check that the reported molar enthalpy carries the correct sign and matches whether the reaction is endothermic or exothermic before scoring the calculation criterion.
- Apply the significant digits standard consistently across all lab reports in the class, since calorimetry data often carries only two or three significant figures.
- When a student's error analysis blames only human error, hold the analysis criterion at Developing rather than Proficient. Look for reference to heat loss to the surroundings or calorimeter heat capacity.
- Score the procedure and calculation criteria independently. A student can execute the experiment well and still make a calculation error, or vice versa.

---
*AILI marking guide · language en · model claude-sonnet-5 · generated 2026-09-17 · id 6c8d60a6-377e-48e8-90af-b88d79c38a9f*

### Sources

- node:n1: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23633)
- node:n2: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23644)
- node:n3: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23649)
- node:n4: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23640)
- node:n5: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23647)
- node:n6: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23635)
- node:n7: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23636)
- node:n8: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23637)
- node:n9: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23643)
- node:n10: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23641)
- node:n11: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23638)
- node:n12: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23634)
- node:n13: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23646)
- node:n14: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23648)
- node:n15: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23639)
- node:n16: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23642)
- node:n17: Chemistry › Chemistry (20, 30) › Chemistry 30 › Unit A: Thermochemical Changes › General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23645)