The Music of Chemistry

Ben McFarland wants to convince his readers that the periodic table is a thing of beauty forever (A World From Dust). He admits that the table as normally presented is “not quite symmetric,” but points out that with a small adjustment “a mathematical pattern appears”: “By row, there are 2, 8, 8, 18, and 18 elements. The pattern continues below, but is obscured by the fact that on most tables 14 elements have been moved out of the 6th and 7th rows.” When they are put where they belong, “these rows have 32 elements each. This can be simplified even more. The rows increase, first by 2, then by 6 more (2 + 6 = 8), then by 10 more (2 + 6 + 10 = 18), then by 14 (2 + 6 + 10 + 18 = 32). The series 2, 6, 10, 14 is the doubles of counting up by odd numbers: 1, 3, 5, 7. Put another way, each row is equal to 2n + 1 with n = integers from 0. So the periodic table is built by counting and adding odd numbers.”

The pattern is not merely mathematical but chemical. The columns organize the elements into families: “all of the elements in the first column will easily lose one electron and usually form single bonds. . . . If the leftmost column is made of jovial, easily reacting elements, the rightmost column is made of elements that keep to themselves. Helium, neon, argon, krypton, and xenon may have the best names of all, but they don’t do much chemistry.” It’s this quality that led Primo Levi to describe the periodic table as “poetry,” each combination rhyming with the others.

Other writers have found analogies with other arts: “Eric Scerri writes that this orderly repetition is almost musical: ‘The elements within any column of the periodic table are not exact recurrences of each other. In this respect, their periodicity is not unlike the musical scale, in which one returns to a note denoted by the same letter, which sounds like the same note but is definitely not identical to it in that it is an octave higher.’” And CP Snow wrote. “For the first time I saw a medley of haphazard facts fall in line and order. All the jumbles and recipes and hotchpotch of the inorganic chemistry of my boyhood seemed to fit themselves into the scheme before my eyes, as though one were standing beside a jungle and it suddenly transformed itself into a Dutch garden.”

It’s a delightful thought that the chemical building blocks of our world might be organized into a symphony.