The given formula unit is MgF₂. The formula unit of MgF₂ represents the lowest whole number ratio of ions present in it.
Dissociation of MgF₂ in water is as follows:
MgF₂ --> Mg²⁺ + 2F⁻
MgF₂ is an ionic compound. It dissolves in water to release one divalent cation of Mg²⁺ and two monovalent F⁻anion.
Thus, when MgF₂ dissolves in water, three total ions produced are Mg²⁺ and 2F⁻.
