Answer:
The correct option is;
Bromine will gain 1 valence electron to become a negative ion
Explanation:
Bromine can be found in period 4 in group 17 of the periodic table and is an halogen
The electron configuration of bromine can be presented as follows;
Electronic configuration 1s²2s²2pā¶3s²3pā¶3d¹ā°4s²4pāµ
Therefore, an atom of bromine has 2 + 5 or 7 electrons in its outermost shell, which makes it have one less electron to complete a full octet structure and therefore, bromine has a strong affinity for electron to complete its octet structure and it is thus a strong oxidizing agent.
When bromine enters into a chemical reaction and gains the one valence electron it becomes a negatively charged ion.