5.3 MAKING SALTS

Those without Na, NH4, or K ions

Insoluble

• Heat the acid - Hot acid has more kinetic energy, so reacts faster with the base • Add the base till no more will dissolve and stir - the base is in excess so we know all the acid has been used up • Filter out excess base • CRYSTALLISE

• Heat solution until crustals start to form - solution becomes saturated • Allow solution to cool in evaporating basin - lowers solubility of salt • Filter out crystals - removes them from excess salt solution in basin • Dry crystals by dabbing with filter paper - removes last traces of water

When alkalis contain Na, K, or NH ions, as you wouldn’t be able to filter them out, like the insoluble base method

• Perform a titration to measure the volumes of acid and alkali that neutralise each other (with an indicator) • Repreat without an indicator, and use the burette to add exactly the right amount for neutralisation • CRYSTALLISE

An insoluble solid that forms inside a solution

Mixing ions up, and seeing insoluble compounds form

Mixing solutions

Ions that aren’t involved in making a percipitate and remain soluble in the solution

Just write the ions involving the precipitation

Just write the ions involving the precipitation

• Filter out salt precipitate • Rinse the salt with water, to wash off traces of leftover solution • Dry the salt by dabbing it with filter paper - removes the last traces of water