Prepare a Soluble Salt II (Edexcel IGCSE Chemistry)

Prepare a soluble salt II

• It is also possible to prepare a sample of a dry salt starting from an acid and an alkali

• A titration can be used for this

Preparation of a soluble salt using a titraion

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