I’m sure most of you have seen today’s Google Doodle but, if not, today would have been the 182nd birthday of creator of the periodic table, Dmitri Mendeleev.
Mendeleev is most known because he organised the known chemical elements by their properties, which allowed him to predict elements which had not yet been discovered, such as gallium and germanium. In 1869, Mendeleev gave a presentation to the Russian Chemical Society, stating his findings:
- The elements, if arranged according to their atomic weight, exhibit an apparent periodicity of properties.
- Elements which are similar regarding their chemical properties either have similar atomic weights (e.g., Pt, Ir, Os) or have their atomic weights increasing regularly (e.g., K, Rb, Cs).
- The arrangement of the elements in groups of elements in the order of their atomic weights corresponds to their so-called valencies, as well as, to some extent, to their distinctive chemical properties; as is apparent among other series in that of Li, Be, B, C, N, O, and F.
- The elements which are the most widely diffused have small atomic weights.
- The magnitude of the atomic weight determines the character of the element, just as the magnitude of the molecule determines the character of a compound body.
- We must expect the discovery of many yet unknown elements–for example, two elements, analogous to aluminium and silicon, whose atomic weights would be between 65 and 75.
- The atomic weight of an element may sometimes be amended by a knowledge of those of its contiguous elements. Thus the atomic weight of tellurium must lie between 123 and 126, and cannot be 128.
- Certain characteristic properties of elements can be foretold from their atomic weights.
However, this isn’t Mendeleev’s only achievement. He carried out research in researcher in the fields of hydrodynamics, meteorology, geology, chemical technology and industrial chemistry, and was one of the founders of the Russian Chemical Society. Mendeleev was even celebrated as a master suitcase maker, which were put together with an adhesive he invented himself. He was also very interested in shipbuilding, and wrote over 40 scientific papers on the subject.
To celebrate the main man’s birthday, Compound Interest have made a graphic showing various trends of the periodic table: