Reaction rates · Grade 10
The iodine clock
ChemAI · Worksheet
NameClassDate
Aim
A colourless mixture that turns blue-black at a moment you can predict.
Before you start: what do you predict will happen? Why?
What you do
| Step | What I observed | |
|---|---|---|
| 1 | Set the amount to 10 mL. Add solution B twice (20 mL) to beaker 1 and wait. | |
| 2 | In beaker 2 add 10 mL of water first, then 10 mL of solution B. | |
| 3 | Compare the two times in the observations: how does concentration change the rate? |
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?