Titrations: analytical technique
I can accurately measure the volume of an acid of an unknown concentration that neutralises an alkali of a known concentration.
Titrations: analytical technique
I can accurately measure the volume of an acid of an unknown concentration that neutralises an alkali of a known concentration.
Lesson details
Key learning points
- In a titration, a trial investigation helps estimate the amount of acid needed to neutralise the alkali.
- Near the end point, add the acid drop by drop whilst swirling the solution in the conical flask to mix.
- Placing a white tile under the conical flask enhances the visibility of the colour change and accuracy of readings.
- Volume readings should be taken at eye level from the bottom of the meniscus.
- Concordant titres are typically within ±0.10 cm³.
Common misconception
Pupils often believe that any small colour change signals the end point, leading to inaccurate titrations.
Emphasise the importance of adding the titrant drop by drop near the end point and ensure pupils understand that the end point is reached only when the colour change is persistent.
Keywords
Titrant - the solution of known concentration added from the burette in titration
Analyte - the solution of unknown concentration in the conical flask in titration
Concentration - the amount of a solute dissolved in a certain volume of solvent
Concordant - readings within a certain range; for titrations, these usually need to be within ±0.10 cm³ of each other
Titre - the volume of titrant needed to reach the end point in a titration
Equipment
burettes, volumetric pipettes/measuring cylinders, mini funnels, conical flasks, 0.1 M solution of HCl and an 'unknown conc' of NaOH, white tiles, pipette fillers, phenolphthalein indicator
Content guidance
- Risk assessment required - chemicals
- Risk assessment required - equipment
Supervision
Adult supervision required
Licence
This content is © Oak National Academy Limited (2024), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).
Video
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Starter quiz
6 Questions
A technique to find volumes of reacting solutions.
The space matter occupies, often in cm³.
When enough solution is added for a complete reaction.
An acid that fully ionises in water.
Exit quiz
6 Questions
Solution of known concentration in the burette.
Solution of unknown concentration in the conical flask.
Amount of solute dissolved in a solvent.
Titres within ±0.10 cm³ of each other.
Volume of titrant needed to reach the end point.