Tom the Atom Book 4: Water Matters.Tom-the-Atom (Carbon atom) introduces to Mary and Henry two brothers, from his same family of Non-Metals: Hydrogen and Oxygen. Henry, Mary, and Tom-the-Atom--by holding hands and saying the magic words-- shrink to a minuscule size. They land in the World of Atoms. Tom-the-Atom introduces, to Mary and Henry, the Hydrogen and Oxygen atoms--his brothers from the same Non-Metals family- and the concept of molecules. Hydrogen has one valence electron or "hand" and one "empty sleeve" (two "hands" or valence electrons will make his small, first, and the only shell full). Oxygen has six "hands" and two "empty sleeves" [eight valence electrons will make his outer (second) shell complete]. The two Hydrogen (H) atoms share one "hand" and one "empty sleeve" with the oxygen (O) atom to form a water molecule (H2O; i.e., H-O-H). Water is a very happy and stable molecule. It is an essential molecule in the world because life could not exist without water. Do you know that more than 65% of your body is water? Water is crucial to life and has many beautiful properties.