Examples of Anions and Cations


The ions they are atoms or molecules that are no longer neutral and have an electrical charge, that is, they are electrically charged particles. To acquire electric charge, neutral particles must give up or accept electrons.

Ions can be:

  • cations. They have a net electrical charge that can be positive (where the neutral atom has lost one or more electrons). For example: cesium cation, mercury cation.
  • anions. They have a negative electrical charge (where the neutral atom has gained one or more electrons). For example: oxide anion, sulfide anion.

The opposite sign ions They can come together to form chemical bonds, such as the ionic bond, which is formed when ions of different signs are electrostatically attracted. This type of bond is strong and ionic compounds form crystal structures.

examples of anions

Anions, in turn, can be:

  • monatomic anions. They are made up of a single atom and have a single negative oxidation state. They are usually nonmetals whose neutral atoms have gained one or more electrons.
  • polyatomic anions. They are made up of a set of atoms whose oxidation state may vary for each individual atom, but the set as a whole has a single oxidation state. They are acids that lost protons or molecules that gained electrons.

The following list exemplifies a series of anions that are frequent in nature, highlighting their oxidation number:

monatomic anions

  1. Hydride anion (H)
  2. Oxide Anion (Otwo-)
  3. Fluoride anion (F)
  4. Chloride Anion (Cl)
  5. Bromide anion (Br)
  6. Iodide anion (Br)
  7. Sulfide Anion (Stwo-)

polyatomic anions

  1. Oxochlorate (I) or hypochlorous anion (ClO)
  2. Chloric trioxochlorate (V) anion (ClO3)
  3. Dioxobromate (III) or bromous anion (BrOtwo)
  4. Tetraoxobromate (VII) or perbromic anion (BrO4)
  5. Oxoiodate (I) or hypoiodose (IO) anion)
  6. Trioxosulfate (IV) or sulfite (SO) anion3two-)

examples of cations

The cations are the positive ions that are characterized by having a deficiency of electrons in the outermost orbitals. Normally they are metals, although sometimes there are non-metals that act as cations.

The size of these cations is less than that of neutral atoms and anions, because the loss of electrons occurs specifically in the outermost part.

The following list shows some common cations and groups them according to their oxidation number.

Cations with oxidation number 1+

  1. Cesium cation (Cs+)
  2. Copper (I) or cuprous cation (Cu+)
  3. Lithium cation (Li+)
  4. Potassium cation (K+)

Cations with oxidation number 2+

  1. Cobalt (II) or cobaltous cation (Co2+)
  2. Copper (II) or cupric cation (Cu2+)
  3. Mercury (II) or mercuric cation (Hg2+)
  4. Lead (II) or plumbose cation (Pb2+)
  5. Nickel (II) or nickelous cation (Ni2+)
  6. Tin (II) or stannous cation (Sn2+)

Cations with oxidation number 3+

  1. Nickel (III) or nickelic cation (Ni3+)
  2. Magnanese (III) or manganous cation (Mn3+)
  3. Chromium (III) or chromous cation (Cr3+)

Cations with oxidation number greater than 3+

  1. Lead (IV) or lead cation (Pb4+)
  2. Manganese (IV) or manganic cation (Mn4+)
  3. Chromium (VI) or chromic (Cr) cation6+)
  4. Manganese (VII) or permanganic (Mn) cation7+)
  5. Tin (IV) or stannic (Sn) cation4+)