Classifying materials · Grade 8
Paper chromatography of inks
ChemAI · Worksheet
NameClassDate
Aim
Separate inks into their dyes and find which dyes are in the unknown ink X.
Before you start: what do you predict will happen? Why?
What you do
| Step | What I observed | |
|---|---|---|
| 1 | Add about 10 mL of water (the solvent). Its level must stay below the pencil start line. | |
| 2 | Wait (speed ×5) until the solvent front is near the top. | |
| 3 | Use the ruler: Rf = distance of the spot ÷ distance of the solvent. Which inks have the same dyes as X? | |
| 4 | Measure the Rf of the red dye (2 decimals). |
Calculation
Measure the Rf of the red dye (2 decimals).
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?