Equations and amounts · Grade 10
Titration: how much acid?
ChemAI · Worksheet
NameClassDate
Aim
Find the exact volume of acid that neutralises 10 mL of base.
Before you start: what do you predict will happen? Why?
What you do
| Step | What I observed | |
|---|---|---|
| 1 | The burette holds 0.5 M hydrochloric acid. Open the tap and let about 8 mL run in. Swirl (Shake) now and then. | |
| 2 | Near the end, turn the tap to drop by drop. Close it as soon as the pink colour disappears and read the burette. | |
| 3 | Calculate: n(NaOH) = 0.5 × 0.010 = 0.005 mol, so you need 10 mL of 0.5 M HCl. Reach it without going past 10.4 mL. | |
| 4 | Calculate c(NaOH) from your end point: c = 0.5 × V(HCl) ÷ 10 mL (mol/L). |
Calculation
Calculate c(NaOH) from your end point: c = 0.5 × V(HCl) ÷ 10 mL (mol/L).
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?