Dmitri Ivanovich Mendeleev (1834-1907) was a Russian chemist famous for his formulation of classification of elements, or what is now called the Periodic Table of Elements (2011). On 6 March 1869, Mendeleev made a formal presentation to the Russian Chemical Society, titled “The Dependence between the Properties of the Atomic Weights of the Elements”, which described elements according to both atomic weight and valence. This presentation stated that: the elements, if arranged according to their atomic weight, exhibit an apparent periodicity of properties; elements which are similar in regards to their chemical properties have atomic weights which are either of nearly the same value (e.g., Pt, Ir, Os) or which increase 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 valence’s, as well as, to some extent, 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; and that 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 (2011).…