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Monatomic ion
Introduction
A monatomic ion is an ion consisting of many of the same atoms. A type I binary ionic compound contains a metal (cation) that forms only one type of ion. A type II ionic compound contains a metal that forms more than one type of ion, i.e., ions with different charges
Common monatomic ions
Common monatomic ions
| Common type I cations | |
|---|---|
| Hydrogen | H+ |
| Lithium | Li+ |
| Sodium | Na+ |
| Potassium | K+ |
| Caesium | Cs+ |
| Beryllium | Be2+ |
| Magnesium | Mg2+ |
| Calcium | Ca2+ |
| Barium | Ba2+ |
| Aluminum | Al3+ |
| Silver | Ag+ |
| Zinc | Zn2+ |
| Common anions | |
|---|---|
| hydride | H− |
| fluoride | F− |
| chloride | Cl− |
| bromide | Br− |
| iodide | I− |
| oxide | O2− |
| sulfide | S2− |
| nitride | N3− |
| phosphide | P3− |
| Common type II cations | ||
|---|---|---|
| Systematic name | Ion | Alternate name |
| iron(III) | Fe3+ | ferric |
| iron(II) | Fe2+ | ferrous |
| copper(II) | Cu2+ | cupric |
| copper(I) | Cu+ | cuprous |
| cobalt(III) | Co3+ | cobaltic |
| cobalt(II) | Co2+ | cobaltous |
| tin(IV) | Sn4+ | stannic |
| tin(II) | Sn2+ | stannous |
| lead(IV) | Pb4+ | plumbic |
| lead(II) | Pb2+ | plumbous |
| mercury(II) | Hg2+ | mercuric |
| mercury(I) | Hg22+* | mercurous |
*note that mercury (I) ions always occur bound together to form Hg2.