Answer:
[tex]\boxed {\boxed {\sf FeBr_3}}[/tex]
Explanation:
We can assume that this is a neutral compound, meaning the charges of the ions are balanced.
We are given: Iron (III) Bromide.
We want to find the chemical formula.
First, find the symbols of the elements.
Next, find the charges on the ions.
The Roman Numeral 3 in parentheses (III). This indicates the iron cation has a charge of +3.
We need to balance out the charge of +3 with the bromine. Bromine can have a charge of +5, +1, and -1. Since we already have a cation (positive ion), bromine must be an anion (negative ion). We also know the charge must be negative to balance out the compound.
But, the charge is only -1. That would still leave the compound unbalanced. Therefore, we must have 3 bromine atoms to balance out the iron. The 3 will become a subscript.
So, put all the information together and write the formula:
FeBr₃
