1 2 3 4 5 6 7 8 9 10 11 Which element in period 4 is the most chemically active non-metal? square

In period 4 of the periodic table, the most chemically active non-metal is bromine (Br). Non-metals tend to gain electrons during chemical reactions, and their reactivity generally increases as you move from left to right across a period. In period 4, bromine is located in group 17 (the halogens), which are known for being highly reactive non-metals. Therefore, the most chemically active non-metal in period 4 is:<br /><br />\(\boxed{\text{Bromine (Br)}}\)