Anion or Anions: They are ions with a negative electric charge, that is, they have gained electrons. Anions have a negative oxidation state, they can be monoatomic and polyatomic.
Summary
[ hide ]
- 1 Monatomic anions
- 2 Polyatomic anions
- 3 Importance and benefits for human health
- 4 Sources
Monatomic anions
They usually correspond to nonmetals that have gained electrons completing their valence shell. These are named using the following nomenclature.
- They are named with the word ion followed by the name of the nonmetal ending in the suffix uro.
| Compound | Name |
| Cl – | Chloride ion |
| H – | Hydride ion |
| S 2- | Sulfur ion |
| N 3- | Nitride ion |
| C 4- | Carbide ion |
Polyatomic anions
They can be considered as coming from a molecule that has lost protons. The following nomenclature can be used to name them.
- For oxanions: they are named with the word ion followed by the name of the nonmetal ending in -ato if it acts with the highest valence, the oxidation number is indicated with a Roman number or ending in -ito if it acts with the lowest valence.
| Compound | Name |
| ClO – | Chlorate ion (I) |
| ClO 2 – | Chlorate Ion (III) |
| ClO 3 – | Chlorate ion (V) |
| ClO 4 – | Chlorate ion (VII) |
- For oxanions with Hydrogen : the name of the oxoanion is preceded by (…) – hydrogen where the prefix (…) indicates the number of hydrogen atoms in each oxoanion.
| Compound | Name |
| PO 4 3- | Phosphate ion (V) |
| HPO 4 2- | Hydrogen phosphate ion (V) |
| H 2 PO 4 2- | Dihydrogen phosphate ion (V) |
- Others: they do not follow a specific rule, the old nomenclature is generally used for them.
| Compound | Name |
| OH – | Hydroxyl ion |
| CN – | Cyanide ion |
| SCN – | Thiocyanate ion |
| CNO – | Cyanate ion |
| MnO 4 2- | Manganate ion |
| MnO 4 – | Permanganate ion |
| CrO 4 2- | Chromate ion |
| Cr 2 O 7 2- | Dichromate ion |
Importance and benefits for human health
Anions in air are as important as vitamins in food and are given such nice names as “The Air Vitamin”, “The Element of Longevity”, “The Air Cleaner” and others. They are also attributed positive effects on human health by neutralizing acid levels in the blood circulation, due to their negative charge they have the ability to absorb dust, particles, bacteria and viruses that have a positive charge and neutralize them, among others.
