This is the Periodic Table
Halogens and Alkali react aggressively
Each period will see new outer shells
While electrons are added moving to the right
Then Cobalt, Nickel coins you get
Selenium and Bromine film
While Krypton helps light up your room
Rubidium and Strontium then Yttrium, Zirconium
Niobium, Molybdenum, Technetium