Answer:
Fe2O3, Fe2S3 and FeCl3
Step-by-step explanation:
The formular shows the number of atoms of element present in the compound. The number of atoms in turn depends on the charges. The goal is to have a neutral compound with oxidation number of zero.
Oxide:
Iron(Fe) has oxidation number (O.N) of +3, oxygen has O.N of -2. The formular with a balanced (Charge = 0) O.N number is; Fe2O3
Sulphide:
Iron(Fe) has oxidation number (O.N) of +3, sulphur has O.N of -2. The formular with a balanced (Charge = 0) O.N number is; Fe2S3
Chloride:
Iron(Fe) has oxidation number (O.N) of +3, chlorine has O.N of -1. The formular with a balanced (Charge = 0) O.N number is; FeCl3