The theory of invisible particles as a building material of matter was developed by Greek philosophers Democritus and Leucippus more than 2,000 years ago. These small indivisible particles were named atoms whereas the early concept of this notion, which was accumulated on experimental base, was created by John Dalton in around 1805. He denoted that atoms made up elements, and “all atoms of an element are alike in weight, and this weight is different from that of any other kind of atom…; atoms of different elements combine in simple whole-number ratios to form chemical compounds” (Mascetta 336).

Early knowledge of atom made an abundance of scientists discover new elements and their properties whereas Dmitriy Mendeleev became the one who initially decided to organize all known elements in the periodic table (see fig. 1). The arrangement of elements had to give some information concerning them. Though modern tables differ from the one shown in the figure; the arrangement of elements remains the same, and “in this early form of the periodic table, within each column some elements were placed toward the left side and some toward the right. With some exceptions, the elements on a given side have some properties” (Ebbing, Gammon 311). In 1871, “he arranged the elements not only by their mass in horizontal rows (periods), but also in vertical columns (groups, also called families) by their valences as well as other chemical and physical characteristics.” (Krebs 26). In the periodic table of Dmitriy Mendeleev published in 1872, spaces were left for undiscovered elements. It is evident that having written the known elements in a row, the scientist could calculate approximate values for the missing ones. The elements of Group III (under aluminum) were named eka-aluminum; they were known to have oxides R2O3. Moreover, they were predicted to have an oxide with the formula Ea2O3.

In conclusion, it is necessary to admit that the fungal development of the periodic table was provoked by numerous discoveries of new elements and conducting a study of their properties. Nowadays, scientists are responsible for its improvement whereas Dmitriy Mendeleev became the author of the periodic table that is widely used now; this was one of the major achievements in chemistry. The descriptive character of the periodic table represents the basic information about elements, their variations, and properties.

arrow_upward