# Enthalpy Changes and Calorimetry Crossword

This puzzle reviews the vocabulary of thermochemistry in Chemistry 30, where students determine and interpret energy changes in chemical reactions ([Topic](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23633)) and explain and communicate those changes ([Topic](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23650)). Terms in this puzzle include enthalpy and ΔH notation ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23638)), calorimetry data used to calculate enthalpy change ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23641)), activation energy shown on energy diagrams ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23653)), and the classification of reactions such as combustion as exothermic ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23643)). Use the clues below to complete the grid before checking your work against the answer key.

## How to play

Fill in the grid using the numbered clues below. Each clue corresponds to a term from Unit A: Energy, Change and Systems. Write one letter per box, reading across or down as indicated by the clue number. Check spelling carefully: several terms are closely related and differ by only a few letters. Do not look at the answer key until you have attempted every clue.

## Puzzle grid

| ■ | 1 | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ |
|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|
| ■ |   | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ |
| ■ |   | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | 2 | ■ | ■ | ■ |
| ■ |   | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ |   | ■ | ■ | ■ |
| ■ |   | ■ | ■ | ■ | 3 | ■ | ■ | ■ | ■ | 4 | 5 |   |   |   |   |   |   |
| ■ |   | ■ | ■ | ■ |   | ■ | ■ | ■ | ■ | ■ |   | ■ | ■ |   | ■ | ■ | ■ |
| 6 |   |   |   |   |   |   |   |   | ■ | ■ |   | ■ | ■ |   | ■ | ■ | ■ |
| ■ |   | ■ | ■ | ■ |   | ■ | ■ | ■ | ■ | ■ |   | ■ | ■ |   | ■ | ■ | ■ |
| ■ | ■ | ■ | ■ | ■ |   | ■ | ■ | ■ | ■ | ■ |   | ■ | ■ |   | ■ | ■ | ■ |
| ■ | ■ | ■ | ■ | 7 |   |   |   |   |   |   |   |   |   |   | ■ | ■ | ■ |
| ■ | ■ | ■ | ■ | ■ |   | ■ | ■ | ■ | ■ | ■ |   | ■ | ■ | ■ | ■ | ■ | ■ |
| ■ | ■ | ■ | ■ | ■ |   | ■ | ■ | ■ | ■ | ■ |   | ■ | ■ | ■ | ■ | ■ | ■ |
| ■ | ■ | ■ | ■ | 8 |   |   |   |   |   |   |   |   |   | ■ | ■ | ■ | ■ |
| ■ | ■ | ■ | ■ | ■ |   | ■ | ■ | ■ | ■ | ■ |   | ■ | ■ | ■ | ■ | ■ | ■ |

## Clues

### Across

4. Chemical process involving breaking and forming of bonds. (8)
6. Standard enthalpy change when one mole of a compound is made from its elements. (9)
7. Experimental technique to measure heat released or absorbed in a reaction. (11)
8. Rapid reaction of a hydrocarbon with oxygen that releases energy. (10)

### Down

1. ΔH symbol used to represent energy change in a reaction. (8)
2. Heat content of a substance at constant pressure. (8)
3. Minimum energy required for reactants to form products. (10)
5. Chemical reaction that releases energy to the surroundings. (10)

## Answer key

- **1 down**: NOTATION
- **2 down**: ENTHALPY
- **3 down**: ACTIVATION
- **4 across**: REACTION
- **5 down**: EXOTHERMIC
- **6 across**: FORMATION
- **7 across**: CALORIMETRY
- **8 across**: COMBUSTION

| ■ | N | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ |
|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|
| ■ | O | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ |
| ■ | T | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | E | ■ | ■ | ■ |
| ■ | A | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | ■ | N | ■ | ■ | ■ |
| ■ | T | ■ | ■ | ■ | A | ■ | ■ | ■ | ■ | R | E | A | C | T | I | O | N |
| ■ | I | ■ | ■ | ■ | C | ■ | ■ | ■ | ■ | ■ | X | ■ | ■ | H | ■ | ■ | ■ |
| F | O | R | M | A | T | I | O | N | ■ | ■ | O | ■ | ■ | A | ■ | ■ | ■ |
| ■ | N | ■ | ■ | ■ | I | ■ | ■ | ■ | ■ | ■ | T | ■ | ■ | L | ■ | ■ | ■ |
| ■ | ■ | ■ | ■ | ■ | V | ■ | ■ | ■ | ■ | ■ | H | ■ | ■ | P | ■ | ■ | ■ |
| ■ | ■ | ■ | ■ | C | A | L | O | R | I | M | E | T | R | Y | ■ | ■ | ■ |
| ■ | ■ | ■ | ■ | ■ | T | ■ | ■ | ■ | ■ | ■ | R | ■ | ■ | ■ | ■ | ■ | ■ |
| ■ | ■ | ■ | ■ | ■ | I | ■ | ■ | ■ | ■ | ■ | M | ■ | ■ | ■ | ■ | ■ | ■ |
| ■ | ■ | ■ | ■ | C | O | M | B | U | S | T | I | O | N | ■ | ■ | ■ | ■ |
| ■ | ■ | ■ | ■ | ■ | N | ■ | ■ | ■ | ■ | ■ | C | ■ | ■ | ■ | ■ | ■ | ■ |

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*AILI game · language en · model claude-sonnet-5 · generated 2026-09-17 · id d17dde3c-fe96-413f-8096-d2330a5ab801*

### Sources

- node:n1: Unit A: Thermochemical Changes (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23632)
- node:n2: General Outcome 1 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23633)
- node:n3: Specific Outcomes for Knowledge (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23634)
- node:n4: Specific Outcomes for Knowledge (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23636)
- node:n5: Specific Outcomes for Knowledge (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23637)
- node:n6: Specific Outcomes for Knowledge (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23638)
- node:n7: Specific Outcomes for Knowledge (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23639)
- node:n8: Specific Outcomes for Knowledge (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23640)
- node:n9: Specific Outcomes for Knowledge (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23641)
- node:n10: Specific Outcomes for Knowledge (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23643)
- node:n11: General Outcome 2 (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23650)
- node:n12: Specific Outcomes for Knowledge (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23652)
- node:n13: Specific Outcomes for Knowledge (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/23653)