One of the most amazing scientific discoveries of the last two centuries was created using nothing more than a pen and a piece of paper by Dmitri Mendeleev in 1869: the periodic table. By chopping up the row and rearranging it in shorter rows with similar elements above each other, he came up with the first version of the periodic table. The Periodic LawMendeleev’s “periodic law” stated that these patterns were part of the essential nature of the elements. The Strange Case of 7 UpMost people know that Coca-Cola originally contained cocaine, but did you know the original version of 7 Up included a compound of the metal lithium, lithium citrate (also used to medicate mood swings)? Sir William Ramsay had already discovered other members of the group of unreactive “noble gases”, including helium, krypton and argon, but the periodic table predicted one more.

Source: The Irish Times June 14, 2019 05:15 UTC