Question

3.) what is the chemical formula for iron (iii) oxide? (1 point) fe₂o₃ feo fe₃o₂

Explanation:

Iron (III) has a charge of +3 (denoted by the Roman numeral III), and oxygen (in oxide form) has a charge of -2. To balance the charges in the compound, we use the criss - cross method. The number of iron atoms (Fe) and oxygen atoms (O) is determined by the absolute values of their charges. The charge of Fe is 3 and O is 2, so we cross these numbers. This gives us 2 Fe atoms (because the charge of O is 2) and 3 O atoms (because the charge of Fe is 3). So the formula is $Fe_2O_3$. $FeO$ is Iron (II) oxide (where Fe has a +2 charge), and $Fe_3O_2$ is not a correct formula for iron (III) oxide.

Answer:

A. $Fe_2O_3$