A detailed visual teaching resource covering the complete procedure and calculations for a simple acid–base titration, using standard hydrochloric acid to determine the concentration of calcium hydroxide in limewater.

The poster takes students through the experiment step by step, including:

correct preparation of a 50 cm³ Grade A burette
rinsing the burette with distilled water and then the titrant
checking that the burette jet contains no air bubbles
removing the filling funnel before beginning the titration
correct use of a 25.0 cm³ bulb pipette and safety pipette filler
preparation of the conical flask and white tile
use of a distilled-water wash bottle
correct reading of the burette and meniscus
identifying the phenolphthalein endpoint
recording results in an appropriate titration table
identifying concordant titres and calculating a mean titre

A complete worked example uses 25.0 cm³ of limewater titrated with 0.0100 mol dm⁻³ hydrochloric acid, giving a mean titre of 23.75 cm³.

The balanced equation and mole ratio are then used to calculate the concentration of calcium hydroxide:

Ca(OH)₂(aq) + 2HCl(aq) → CaCl₂(aq) + 2H₂O(l)

[Ca(OH)₂] = 4.75 × 10⁻³ mol dm⁻³

The resource also develops students’ understanding of apparatus uncertainty, including the uncertainties associated with Grade A burettes and bulb pipettes, calculating percentage uncertainty and combining percentage uncertainties.

A final comparison demonstrates why very small titres produce much larger percentage uncertainties, an important consideration when planning quantitative experiments.

Ideal for GCSE and A-level Chemistry, practical skills, quantitative chemistry, revision and preparation for practical-based examination questions.

Free classroom resource from ACE Chemistry.