A reseacher reports Br2- ion has been detected. Which answer is most consistent with the formation of these ions?

Question

1. All of the above statements.
2. The Br2- ion must have nine outer electrons.
3. The bromine atom gained two electrons to form the ion.
4. The Br2- ion is not expected to be a stable ion of bromine

Answer 1

3. The bromine atom gained two electrons to form the ion.