Answer:
Diiron trioxide or iron(3+) oxide or iron(III) oxide
Explanation:
The IUPAC provides three acceptable names for binary compounds
Multiplicative prefixes
Use the multiplicative prefixes mono-, di-, tri-, etc. to indicate the numbers of each ion in the compound.
Since the ratio is Fe:O = 2:3, the name is diiron trioxide.
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Charge numbers
The charge number is the magnitude of the ionic charge.
Write it in Arabic numerals followed by the sign of the charge. Include it in parentheses immediately after the name of the ion, without a space.
Since Fe has a charge of 3+, the name is iron(3+) oxide.
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Oxidation numbers
Indicate the oxidation number of an element by a Roman numeral in parentheses immediately following the name of the ion, with no spaces.
Since the oxidation number of Fe is +3, the name becomes iron(III) oxide.
