The formula unit for the ionic compound, ferrous bromide, consists of which of the following?

Question

? 1 Fe2- ion and 1 Br2+ ion
? 1 Fe3+ ion and 3 Br- ions
? 2 Fe3+ ions and 3 Br2- ions
? 1 Fe2+ ion and 2 Br- ions
? 1 Fe2+ ion and 1 Br2- ion

Answer 1

The correct formula unit for ferrous bromide consists of one Fe²⁺ ion and two Br⁻ ions. Therefore, the correct answer is:

1 Fe²⁺ ion and 2 Br⁻ ions

This compound can be represented by the formula FeBr₂, indicating that for each iron (Fe) ion in the +2 oxidation state, there are two bromide (Br) ions in the -1 oxidation state to balance the charges.