![]() There are short versions, long versions, circular versions, spiral versions and even three-dimensional versions. A simple search of the internet will reveal all sorts of versions of the periodic table. It would be understandable to think that this would be the end of the matter. By the 1940s, most textbooks featured a periodic table similar to ones we see today, as shown in the figure below. But the latter now followed from the arrangement of electrons repeating in so-called "shells" at regular intervals. It would not be until the early 20th century, after the structure of the atom had been established and following the development of quantum theory, that a theoretical understanding of its structure would emerge.Įlements were now ordered by atomic number (the number of positively charged particles called protons in the atomic nucleus), rather than by atomic mass, but still also by chemical similarities. ![]() Importantly, Mendeleev's periodic table had been derived empirically based on the observed chemical similarities of certain elements. Something seemed to repeat and by placing chemically similar elements next to each other, a two-dimensional table could be constructed. ![]() But chemists were aware that certain elements had rather similar chemical properties: for example lithium, sodium and potassium or chlorine, bromine and iodine. Simple lists, of course, are one-dimensional in nature. And by the 1860s, it was possible to list the known elements in order of their relative atomic mass-for example, hydrogen was 1 and oxygen 16. By the early 19th century, there was good circumstantial evidence for the existence of atoms. By the late 18th century, chemists were clear about the difference between an element and a compound: elements were chemically indivisible (examples are hydrogen, oxygen) whereas compounds consisted of two or more elements in combination, having properties quite distinct from their component elements. Let's first consider how the periodic table was developed. However, two scientists in Moscow, Russia, have recently published a proposal for a new order. Given the table's importance, one might be forgiven for thinking that the ordering of the elements were no longer subject to debate. It would be hard to overstate its importance as an organising principle in chemistry-all budding chemists become familiar with it from the earliest stages of their education. After many new rounds of proof reading, the completed design was printed on the resin panels displayed in the office.The periodic table of the elements, principally created by the Russian chemist, Dmitry Mendeleev (1834-1907), celebrated its 150th anniversary last year. We consider it good fortune to have been able to incorporate these latest recommendations into the table. It recommended that atomic weights for Boron, Carbon, Chlorine, Hydrogen, Lithium, Nitrogen, Oxygen, Sulfur, Silicon and Thallium span intervals (shown, for example, for Nitrogen as 14.00643–14.00728), due to variation in isotopic composition of their stable isotopes. Just as we were completing it, the International Union of Pure and Applied Chemistry published its technical report, “Atomic weights of the elements 2009” (Wieser & Coplen, 12 December 2010). Everyone in the department enthusiastically helped with this task. Her innovative concept allowed us to break with convention by partitioning the table itself into six portions.Īt this point we thought that the only thing left to do was to check and recheck all entries for errors. It was then that Kristine mentioned her plan to have the table printed on six resin panels. With that done, the next step was to assemble the elements into the traditional periodic table format, adapted to the dimensions of the wall in the new chemistry office. (The dark chevron indicates that at room temperature Xenon is a gas.) The box for Xenon shows what we settled on, using the typeface Adobe Myriad Pro. The first step in the new design was to settle on the format of the element boxes. The tools I used to create that original Periodic Table have been lost in the sands of digital time, and so it was necessary to begin anew, using the latest version of Adobe Illustrator. I was thinking of the very nice Periodic Table that you created years ago, and that has been much used in our Department. “I received an e-mail from our Chair, John Straub, in which he related designer Kristine Stoller’s idea for a periodic table in the new office. In addition to his theoretical and physical chemistry expertise, Professor Dill is an accomplished photographer, who received a Kodak Award in 2006. When we needed a graphically compelling representation of the Periodic Table for the Chemistry front office, we turned to Professor Dan Dill.
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