Identifying substances · Grade 10
Coloured precipitates
ChemAI · Worksheet
NameClassDate
Aim
Identify metal ions from the colour of their hydroxides, and sulfate with barium.
Before you start: what do you predict will happen? Why?
What you do
| Step | What I observed | |
|---|---|---|
| 1 | Add sodium hydroxide to tube 1 (Cu²⁺). | |
| 2 | Add sodium hydroxide to tube 2 (Fe³⁺). | |
| 3 | Add sulfuric acid to tube 3 (Ba²⁺). | |
| 4 | Bonus: add hydrochloric acid to tube 1. What happens to the blue precipitate? |
Questions
- Write a word or symbol equation for one reaction you observed.
- Explain your most important observation using particles, ions or energy.
- Was your prediction right? What would you change to get a more reliable result?