Iron Phosphide
Fe - Iron P - Phosphorus
3 and 2 refer to how many atoms there are to make the compound neutral.
Phosphorus has a charge of -3 and Iron has a charge of +2.
*Note: Iron can have two charges, +3 and +2.
Iron with a positive charge of +3 is called Iron (III) or Fe (III)
Iron with a positive charge of +2 is called Iron (II) or Fe (II)
In this case it has a charge of +2. Also remember that Fe (III) and Fe (II) is represented by Roman Numerals NOT numbers.
~Hope that answered your question.
The chemical formula for iron(II) phosphide is Fe3P2. It is composed of two phosphorus atoms for every three iron atoms.
The formula for Iron II Phosphide is Fe3P2. It consists of one iron (Fe) atom and two phosphorus (P) atoms.
Fe3PO4
The chemical formula for Iron (II) phosphide is Fe3P2.
There are a umber of different oxides of iron. It depends of the oxidation state of iron. Hematite is Fe2O3, iron(III) oxide. Magnetite is Fe3O4 (diron(II) diron(III) oxide. There is also FeO, iron(II) oxide.
FeP. Iron(III) means that the iron has an oxidation state of 3, and could be considered to be Fe3+. Phosphides generally contain P3- and this is true for the group1 and group 2 metals There is one iron phosphide Fe3P used as a semiconductor, so it is not ionic! You cannot use oxidation number nomenclature on that compound you have to go the "triiron monophosphide" route instead. I do not think there is actually a compound with the formula FeP. Naming phosphides using the oxidation state nomenclature is risky, phosphorus forms many different "ions" and also forms binary compounds where the phosphorus is "interstitial" .