Answer:
O Group 7A, Period 4
Explanation:
To find the location of bromine on the periodic table, we must known its period and group on the periodic table.
Bromine is made up of 35 electrons.
Its electronic configuration is:
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁵
From this configuration, the number of energy levels here is 4 so the element bromine is in period 5
Since the number of valence electrons is 7, it belongs to group 7
So, period 4 and group 7 is the right choice
