Here's how to determine the formula for the ionic compound formed between magnesium and fluorine:

* Charges: Magnesium (Mg) has a +2 charge (Mg²⁺), and fluorine (F) has a -1 charge (F⁻).

* Balancing: To balance the charges, we need two fluoride ions (2 x -1 = -2) for every magnesium ion (+2).

* Formula: The resulting formula is MgF₂.

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