The chemical formula Fe(NO2)3 represents the compound iron(III) nitrite. The compound contains one atom of iron, represented by Fe, three atoms of nitrogen, represented by N, and six atoms of oxygen, represented by O.
In the name iron(III) nitrite, the Roman numeral III indicates the plus three charge on the iron ion. The term nitrite indicates a nitrogen atom bonded with three two oxygen atoms for a total charge of minus one. When the two ions bond together, three ions of nitrite are required to balance the charge from one ion of iron(III). Iron(III) nitrite is sometimes known as ferric nitrite. It has a molar mass of 193.86 grams per mole.