1. Identify the Charges:
* Aluminum (Al) forms a +3 ion (Al³⁺)
* Sulfur (S) forms a -2 ion (S²⁻)
2. Find the Least Common Multiple (LCM):
* The LCM of 3 and 2 is 6.
3. Determine the Subscripts:
* To achieve a +6 charge, you need two Al³⁺ ions (2 x +3 = +6).
* To achieve a -6 charge, you need three S²⁻ ions (3 x -2 = -6).
4. Write the Formula:
The formula for the ionic compound is Al₂S₃.
