Prepare a Salt by Titration (Edexcel GCSE Chemistry)

Prepare a Salt by Titration

• If salts are prepared from an acid and a soluble reactant then a titration technique must be used

• In a titration, the exact volume of acid and soluble reactant are mixed in the correct proportions so that all that remains is the salt and water

Preparing a Salt by Titration

Aim:

To prepare a sample of a dry salt starting from an acid and an alkali

Diagram:

Diagram showing the apparatus needed to prepare a salt by titration

 Method:

• Use a pipette to measure the alkali into a conical flask and add a few drops of indicator (phenolphthalein or methyl orange)

• Add the acid into the burette and note the starting volume

• Add the acid very slowly from the burette to the conical flask until the indicator changes to appropriate colour

• Note and record the final volume of acid in burette and calculate the volume of acid added (starting volume of acid - final volume of acid)

• Add this same volume of acid into the same volume of alkali without the indicator

• Heat to partially evaporate, leaving a saturated solution

• Leave to crystallise decant excess solution and allow crystals to dry

Results:

A dry sample of a salt is obtained