These are chemical equations representing the formation of different compounds using a combination of iron (II) sulfate (FeSO4) and iron (II) salts such as iron (II) nitrate (Fe(NO3)2), iron (II) hydroxide (Fe(OH)2), and iron (II) chloride (FeCl2).

FeSO4 + Fe(NO3)2 → FeSO4-Fe(NO3)2FeSO4 + Fe(OH)2 → FeSO4-Fe(OH)2FeSO4 + FeCl2 → FeSO4-FeCl2

These equations show the formation of coordinated compounds between iron (II) sulfate and various iron (II) salts.