To combine the ions Sr²⁺ (strontium) and N³⁻ (nitride) to form a neutral compound, you'll need to balance the charges.
- Strontium has a +2 charge (Sr²⁺).
- Nitrogen has a -3 charge (N³⁻).
To balance the charges, you can use the lowest common multiple of the charges, which is 6. This means you will need:
- 3 strontium ions (3 x +2 = +6)
- 2 nitride ions (2 x -3 = -6)
Therefore, the formula for the compound formed by these ions is:
\[ \text{Sr}_3\text{N}_2 \]
This indicates that the compound consists of 3 strontium ions and 2 nitride ions.