* Identify the hydroxide ion: The formula shows a hydroxide ion (OH-) with one oxygen atom.
* Count the hydroxide ions: The subscript '3' after the parentheses indicates there are three hydroxide ions in each formula unit.
* Multiply: Since each hydroxide ion has one oxygen atom, and there are three hydroxide ions, there are a total of 3 * 1 = 3 oxygen atoms in a formula unit of Aluminum Hydroxide.
