The formula Al(NO₃)₃ represents aluminum nitrate. Here's how to break down the formula to find the number of nitrogen atoms:

* Parentheses: The parentheses indicate that everything inside them is multiplied by the subscript outside.

* Subscripts: The subscript "3" outside the parentheses means there are three nitrate (NO₃) groups.

* Nitrogen within the nitrate group: Each nitrate group (NO₃) contains one nitrogen atom.

Therefore, the formula Al(NO₃)₃ indicates a total of 3 nitrogen atoms.