What is the chemical formula for iron(lll) oxide?

1 Answer
Jan 25, 2016

Ferric oxide, #Fe_2O_3#.

Explanation:

What's the other name for this stuff?

The iron is assumed to be in a #+III# oxidation state, i.e. we treat it as #Fe^(3+)#. Oxygen generally assumes a #-II# oxidation state, i.e. #O^(2-)# and it does here.

We know that it is a neutral species, so we cross multiply the presumed charges to get the given formula: #3xx(-2) +2xx3=0#, as required.