| Revision as of 01:39, 26 November 2009 editH Padleckas (talk | contribs)Pending changes reviewers5,975 edits Redirect to Ferrous | Revision as of 12:42, 2 April 2019 edit undoJorge Stolfi (talk | contribs)Autopatrolled, Extended confirmed users, Rollbackers27,608 edits Starting to create a full iron(II) article about iron in the 2+ oxidation stateTag: Removed redirectNext edit → | ||
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| In ], '''iron(II)''' refers to the ] ] in its +2 ]; meaning an atom of iron that has lost two of its electrons. In ] (salts), such an atom may occur as a separate ] (positive ion) denoted by '''Fe<sup>2+</sup>'''. | |||
| #REDIRECT ] | |||
| The adjective '''ferrous''' or the prefix '''ferro'''- is often used to specify such compounds — as in "ferrous chloride" for ], {{chem2|FeCl2}}. The adjective "ferric" is used instead for ] salts, containing the cation or Fe<sup>3+</sup>. The word ferrous is derived from the ] word ''ferrum'' for iron. | |||
| Iron(II) atoms may also occur as ]es, such as the polymer ] ], {{chem2|''n''}} or {{chem2|''n''}}; and ]s, such as the neutral molecule ], {{chem2|Fe(C2H5)2}} or {{chem2|2}}. | |||
| Iron is almost always encountered in the oxidation states 0 (as in the metal), +2, or +3. Solid iron(II) salts are relatively stable in air, but in the presence of air and water they tend to ] to iron(III) salts that include ] ({{chem2|HO(-)}}) or ] ({{chem2|O(2-)}} anions. | |||
Revision as of 12:42, 2 April 2019
In chemistry, iron(II) refers to the element iron in its +2 oxidation state; meaning an atom of iron that has lost two of its electrons. In ionic compounds (salts), such an atom may occur as a separate cation (positive ion) denoted by Fe.
The adjective ferrous or the prefix ferro- is often used to specify such compounds — as in "ferrous chloride" for iron(II) chloride, FeCl2. The adjective "ferric" is used instead for iron(III) salts, containing the cation or Fe. The word ferrous is derived from the Latin word ferrum for iron.
Iron(II) atoms may also occur as coordination complexes, such as the polymer iron(II) oxalate dihydrate, [Fe(C2O4)(H2O)2]n or [Fe·C2O2−4·H2O]n; and organometallic compounds, such as the neutral molecule ferrocene, Fe(C2H5)2 or [Fe][C5H−5]2.
Iron is almost always encountered in the oxidation states 0 (as in the metal), +2, or +3. Solid iron(II) salts are relatively stable in air, but in the presence of air and water they tend to oxidize to iron(III) salts that include hydroxide (HO) or oxide (O anions.