Year 8 Science · Unit 3 · Lesson 2
Foundation Worksheet
Learning Goals
Match each change to its type and evidence
Draw a line from each change to its correct type AND its key evidence. Or write the matching letters in the "Your answer" column.
| Change | Type (your answer) | Evidence (your answer) | Types & Evidence options |
|---|---|---|---|
| Burning magnesium ribbon |
Types: P = Physical change C = Chemical change Evidence: A. New white solid forms B. Substance can be melted & re-solidified C. Salt crystals re-appear on evaporation D. Gas and new flavour compounds form E. Original shape lost but substance unchanged F. Reddish-brown new substance forms |
||
| Crushing an aluminium can | |||
| Dissolving salt in water | |||
| Iron nail left in rain | |||
| Melting chocolate | |||
| Baking bread dough |
Sort it!
Write each change from the pool into the correct category box. Watch out for the tricky cases!
Physical change
Chemical change
Dissolving and digestion are intentionally tricky — think: is a new substance formed?
1. A student says "rusting is just a physical change because iron is still iron — it just changed colour." Explain why this is incorrect using the key test for chemical change.
2. At BlueScope Steel in Port Kembla, rolling hot steel into sheets is a physical change, but converting iron ore to iron in a blast furnace is a chemical change. State one difference between these two processes at the particle level.
Wrap Up
In one sentence, what was the main idea of this lesson?