Year 10 Science · Unit 2 · Lesson 6
Foundation Worksheet
Learning Goals
Match each term to its definition
Draw a line connecting each term on the left to its correct definition on the right. Or write the matching letter next to each term.
| Term | Your answer | Definition |
|---|---|---|
| Synthesis reaction | A. A substance in a chemical equation that is formed by the reaction | |
| Decomposition reaction | B. A reaction that releases energy to the surroundings (usually as heat or light) | |
| Reactant | C. A chemical reaction where two or more substances combine to form one product (A + B → AB) | |
| Product | D. A representation using names of substances to show what reacts and what forms | |
| Word equation | E. A reaction where one substance breaks down into two or more simpler products (AB → A + B) | |
| Exothermic | F. A starting substance that takes part in a chemical reaction |
Sort it!
Write each reaction from the pool into the correct category box. One reaction may not fit either category, write it in "Neither" if so.
Synthesis
Decomposition
Neither
1. The Haber process combines nitrogen gas and hydrogen gas to form ammonia (NH₃). Identify this as a synthesis or decomposition reaction, and write the word equation. Predict whether this reaction is likely to be exothermic or endothermic, and explain your reasoning using the general energy pattern for this reaction type.
2. In 1774, Joseph Priestley heated mercury(II) oxide and discovered oxygen. Identify this as synthesis or decomposition, write the word equation, and state whether the reaction was endothermic or exothermic. Give a reason for your energy classification.
Wrap Up
In one sentence, what was the main idea of this lesson?