Practise titration in an online chemistry lab

Take the readings yourself. Follow the indicator, decide when to stop and use your measured titre to work out an unknown quantity.

Choose how to practise

Start with Tutorial from the laboratory menu to learn the apparatus and FlaskLabs controls. Use Presets for a prepared reaction. Challenge combines a practical with calculation and method questions. In Freedom, choose supported solutions and configure concentrations, volumes and an indicator.

From a burette reading to a titre

1. Check which solution is in the flask and which is in the burette. Record the initial burette reading before adding titrant.
2. Mix the solution as you add titrant. Use a rough run to locate the endpoint, then approach it carefully in later runs.
3. Record the final burette reading. The titre is the final reading minus the initial reading; it is the volume delivered, not the volume remaining.
4. Repeat the practical and choose concordant accurate titres using the tolerance specified by the exercise. Do not include the rough run in the accurate mean.

Understand the endpoint

An indicator endpoint is the observed colour change used to stop a titration. The equivalence point is the stoichiometric point where the reactants have combined in the equation’s mole ratio. They are related, but not identical. Choose an indicator appropriate to the reaction and follow the selected experiment’s endpoint instructions.

The library includes acid–base titrations, carbonate solutions, permanganate redox and prepared hydrated materials. Each preset explains the reagents and expected endpoint before you open the experiment.

A worked calculation

Suppose 25.00 cm³ of hydrochloric acid reacts with a mean titre of 20.00 cm³ of 0.1000 mol dm⁻³ sodium hydroxide. For HCl + NaOH → NaCl + H₂O, the mole ratio is 1:1.

Moles of NaOH = 0.1000 × (20.00 ÷ 1000) = 0.002000 mol. The acid therefore contains 0.002000 mol in 0.02500 dm³, giving a concentration of 0.08000 mol dm⁻³. Other reactions need their own balanced equation; do not assume every titration has a 1:1 ratio.

What a simulation can help with

You can rehearse the sequence, recognise endpoints and connect observations to calculations. A virtual lab cannot replace supervised experience of handling glassware, chemical safety or the full uncertainty of physical measurements. Use it alongside school laboratory work.

Preparing for an exam? Read our Cambridge 9701 practical practice guide.