Making salts (Chemistry)

Outline the 4 key steps

1. Add excess solid (copper oxide/carbonate) to warm acid → stops reacting

2. Filter → removes unreacted solid

3. Evaporate some water using a Bunsen burner

4. Leave to crystallise → dry crystals

Why add the solid in excess?

To make sure ALL the acid reacts — no acid left over ✅

Why warm the acid first?

Speeds up the reaction — particles move faster, more collisions ✅

What does filtration remove?

The unreacted/excess insoluble solid ✅

Why don't we evaporate ALL the water?

Heating to dryness would decompose/damage the salt — leave it to form crystals slowly instead

Why might your crystals be impure?

Didn't filter properly / didn't use excess solid / evaporated too much water