Acids, bases and salts · Grade 11
Neutralisation with an indicator
ChemAI · Worksheet
NameClassDate
Aim
Turn a pink base colourless by adding acid, and watch the temperature rise.
Before you start: what do you predict will happen? Why?
What you do
| Step | What I observed | |
|---|---|---|
| 1 | Add phenolphthalein to the sodium hydroxide. | |
| 2 | Add hydrochloric acid, 5 mL at a time, until the pink colour disappears. | |
| 3 | Read the thermometer: how much did the temperature rise? | |
| 4 | By how many °C did the temperature rise? |
Calculation
By how many °C did the temperature rise?
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?