The formula unit for the ionic compound, cadmium fluoride, consists of which of the following?

Question

? 1 Cd+ ion and 1 F- ion
? 1 Cd2- ion and 2 F+ ions
? 1 Cd2+ ion and 1 F2- ion
? 2 Cd+ ions and 1 F2- ion
? 1 Cd2+ ion and 2 F- ions

Answer 1

The correct formula unit for the ionic compound cadmium fluoride is:

1 Cd²⁺ ion and 2 F⁻ ions.

This is because cadmium (Cd) commonly forms a +2 charge (Cd²⁺), and fluoride (F) has a -1 charge (F⁻). To balance the charges, one Cd²⁺ ion pairs with two F⁻ ions, resulting in the formula unit CdF₂.