The symbol of the cation of FeCl2 is Fe2+. A cation is a positively charged ion and to find the formula of any compound you must balance the cations with the anions.
There is no symbol for FeCl2 as it is a compound. The name of the compound is iron II chloride
Fe2O3 is an iron oxide, a molecule; the valence of iron here is 3+.
Iron sulfide is not a cation.
The cation for FeCl2 is Fe^2+
FeCl2
Lithium bromide (LiBr) is a compound, not a cation. The cation is Li+.
The cation is Mn(3+).
The chemical formula (not symbol) of potassium bicarbonate is KHCO3.
Au3+
FeCl2
FeCl2, FeCl3
The chemical symbol for iron is Fe, and the symbol for chlorine is Cl. If you meant when they are combined, there are two possibilities: FeCl2 for ferrous chloride or FeCl3 for ferric chloride.
The ferrous chloride is FeCl2.
Lithium bromide (LiBr) is a compound, not a cation. The cation is Li+.
The cation of chromium is Cr3+.
The cation is Mn(3+).
The chemical formula (not symbol) of potassium bicarbonate is KHCO3.
The symbol of calcium is Ca.
Au3+
Cu
It is the iron(II) cation. The Fe atom loses two electrons to become doubly positively charged Fe2+ cation. Some of the compounds it might form are FeSO4 and FeCl2.