Answer :
Chlorine.
You can work this out by counting along the periodic table in rows. Chlorine falls as the 5th element in the 3rd down row of the p block (left hand side) of the periodic table.
You can work this out by counting along the periodic table in rows. Chlorine falls as the 5th element in the 3rd down row of the p block (left hand side) of the periodic table.