Tom-the-Atom represents the Carbon Atom, the most crucial atom in the Universe. A series of illustrated science books for children and adolescents. The young reader will become familiar with the world of atoms, which make up all the material in the Universe; the Earth, the planets, the stars, and you and me. The young reader is invited to become part of the World of Atoms and to develop his/her understanding of how atoms form everything. Tom the Atom, Book 9: Meet Iron the lion!You will meet Atoms in Group 3B (Columns 3 to 12 in the Periodic Table). To explain their character, Tom-the-Atom introduces the concept that shells have subshells. Tom-the-Atom calls a larger atom who belongs to the Transition Metals large Family, Iron, Fe. Tom-the-Atom explains how challenging it is to predict the characters of atoms in Group 3B. That is because their Nature depends on who they interact with.