Geography is Destiny

     Sam Kean breaks down the Periodic Table of the Elements by stripping away all of the "clutter". It was 18 columns, and seven rows, and none of the blocks of elements are interchangeable. Seventy-five percent are metals-cold, gray solids at room temperature. Some columns on the right side contain gases, while mercury and bromine are the only elements that are liquid at room temperature.
     A guy named Plato, from ancient Greece, developed a theory of "forms", where all objects are shadows of one ideal type. One of these forms, for helium, was discovered in 1911 when a Dutch-German scientist cooled mercury until the system lost all electrical resistance. And then in 1937, a Russian-Canadian turned helium into a superfluid. Helium is an example of "element-ness" (part of Plato's theory) as it cannot be broken down and it has enough electrons to fill its outermost shell. We have a lot of our knowledge of electrons thanks to a scientist named Lewis, who "spent his life refining how an atom's electrons work in many contexts." He also changed the definitionof an acid from a proton donor to an electron stearler, because some substances act like acids without relying on hydrogen.
     After this new theory, scientists tried to see how strong acids could be. A boron-based acid has a pH of -18, although there are wrose acids based on antimony, an element with a very "colorful" past. Antimony has been used for mascara to help women give the evil eye, wall paint, laxaties, and more; all because of its "sexual properties." When they finally got a handle on it, they were able to mix antimony pentafluoride with hyrofluoric acid to produce a substance with a pH of -31. The strongest solo acid, however, remains as the boron-based carborane.
     Going back to the periodic table, as you move across horizontally, each of the elements have one more electron than the element to the left. On the left side, elements put electron in an s-shell, which only holds two electrons. Elements on the right side put their extra electrons in a p-shell, which can hold six electrons. Together these two shells add up to the eight electrons an element wants in its outer shell. Transition metals, the elements in the middle of the table, start to put their electrons in d-shells. These shells hold up to ten electrons, and they are often buried beneath other layers. Some of these hidden electrons may rise up and react with other substances, but most of the time they tend to stay hidden and cause some elements to appear identical. The next shell, the f-shell, "begins to appear in the first of the two free-floating rows of metals beneath the periodic table, called the lanthanides. This shell gets buried deeper than the d-shells and this makes them more like each other and they can barely be told apart.
     This system of electrons drives the periodic table. But you can't ignore the nucleus, the part of the atom that accounts for most of the weight of an atom. Maria Goeppert from Germany began working with the nuclues in 1948. She suggested that protons and neutrons sit in shells in the nuclues, just like electrons. Her nuclear shell model won her a lot of credit she had been previously denied.
 
     I know this is a lot to read, but it is really quite interesting if you're looking to expand your knowledge of the basic principles of the Periodic Table of the Elements. Enjoy!