The insoluble reactant chosen depends upon the particular salt required. For example, copper does not react with dilute acids, so copper salts are made using copper(II) oxide or copper(II) carbonate, not copper metal. On the other hand, sodium is too reactive to be used safely - again the metal is not used to make sodium salts.
As the reaction between metals and acids produces flammable hydrogen, chemists usually make salts by reacting a metal oxide or a metal carbonate with an acid.
The name of a salt has two parts. The first part comes from the metal, metal oxide or metal carbonate. The second part comes from the acid:
The table shows some examples of the salts produced by different combinations of insoluble reactants and acids.
|Hydrochloric acid||Sulfuric acid||Nitric acid|
|Copper(II) oxide||Copper(II) chloride||Copper(II) sulfate||Copper(II) nitrate|
|Aluminium hydroxide||Aluminium chloride||Aluminium sulfate||Aluminium nitrate|
|Zinc carbonate||Zinc chloride||Zinc sulfate||Zinc nitrate|
This method shows how a soluble salt is produced from an acid and an insoluble reactant. To illustrate the method, hydrochloric acid and zinc carbonate are used: