Naming salts
A saltA compound formed by neutralisation of an acid by a base, eg a metal oxide, as the result of hydrogen ions in the acid being replaced by metal ions or other positive ions. Sodium chloride, common salt, is one such compound. is any compoundA substance formed by the chemical union of two or more elements. formed by the neutralisationThe reaction between an acid and a base to form a salt plus water. of an acidCorrosive substance which has a pH lower than 7. Acidity is caused by a high concentration of hydrogen ions. by a baseA substance that reacts with an acid to neutralise it and produce a salt..
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.
You can always work out the name of the salt by looking at the reactants:
- nitric acid always produces salts that end in nitrate and contain the nitrate ion, NO3–
- hydrochloric acid always produces salts that end in chloride and contain the chloride ion, Cl–
- sulfuric acid always produces salts that end in sulfate and contain the sulfate ion, SO42–
For example, if potassium oxide reacts with sulfuric acid, the products will be potassium sulfate and water.
The table shows some more examples.
| Metal | Acid | Salt | |||
| Sodium hydroxide | reacts with | Hydrochloric acid | to make | Sodium chloride | |
| Copper(II) oxide | reacts with | Hydrochloric acid | to make | Copper(II) chloride | |
| Sodium hydroxide | reacts with | Sulfuric acid | to make | Sodium sulfate | |
| Zinc oxide | reacts with | Sulfuric acid | to make | Zinc sulfate | |
| Sodium hydroxide | reacts with | Nitric acid | to make | Sodium nitrate | |
| Copper(II) carbonate | reacts with | Nitric acid | to make | Copper(II) nitrate |
| Metal | Sodium hydroxide |
|---|---|
| reacts with | |
| Acid | Hydrochloric acid |
| to make | |
| Salt | Sodium chloride |
| Metal | Copper(II) oxide |
|---|---|
| reacts with | |
| Acid | Hydrochloric acid |
| to make | |
| Salt | Copper(II) chloride |
| Metal | Sodium hydroxide |
|---|---|
| reacts with | |
| Acid | Sulfuric acid |
| to make | |
| Salt | Sodium sulfate |
| Metal | Zinc oxide |
|---|---|
| reacts with | |
| Acid | Sulfuric acid |
| to make | |
| Salt | Zinc sulfate |
| Metal | Sodium hydroxide |
|---|---|
| reacts with | |
| Acid | Nitric acid |
| to make | |
| Salt | Sodium nitrate |
| Metal | Copper(II) carbonate |
|---|---|
| reacts with | |
| Acid | Nitric acid |
| to make | |
| Salt | Copper(II) nitrate |
To write the symbol equations for the reactions of acids with these four different bases, you will need to learn the formulae of common substances, and how to write formulae from ions, both of which are covered in The nature of substances and chemical reactions.