Question

What is the formula for iron (III) oxide?

Answer 1

Is it not `Fe_2O_3`, i.e. `"ferric oxide....."`

Explanation:

The `+III` oxidation states denotes the `"ferric ion..."` Rust is thus formally `2xxFe^(3+)+3xxO^(2-)`, the which formulation gives a NEUTRAL salt. Rust prevention is a HUGE industrial and commercial concern....

Answer 2

`Fe_2O_3`

Explanation:

To name a compound in which the first element is a transition metal and there are roman numerals, find out the charge of the non-transition metal. In this case, if oxygen were to get 8 valence electrons, from its typical 6, it would gain 2. Electrons have a negative charge so its charge would be -2. There are 3 oxygen, as stated by the roman numerals. The resulting answer would be `Fe_2O_3`. If you find that confusing here's a diagram on naming compounds like this and others.