* Sodium (Na) is a Group 1 element, meaning it has a +1 charge when it forms an ion (Na⁺).
* Oxygen (O) is a Group 16 element, meaning it has a -2 charge when it forms an ion (O²⁻).
To form a neutral compound, we need the charges to balance. This means we need two sodium ions (2 x +1 = +2) for every one oxygen ion (-2) to achieve a net charge of zero.
Therefore, the correct formula for sodium oxide is Na₂O, not X₂Y.
