Origin and evolution of periodic table
The first periodic table was created before the discovery of the subatomic particles. The table arranges elements into vertical columns (Groups) andhorizontal rows (Periods) to display these commonalities.
Antoine Lavoisier introduced the system of chemical nomenclature. He made a list of 33 elements, or substances that could not be broken downfurther. Lavoisier himself grouped them into four categories on the basis of their chemical properties:
1. Simple substances belonging to all the kingdoms of nature, which may be considered asthe elements of bodies (gases),
2. Oxydable and Acidifiable simple Substances not Metallic (nonmetals),
3. Oxydable and Acidifiable simple Metallic Bodies (metals),
4. Salifiable simpleEarthy Substances (earths).
Since the old achemical symbols were not fit to use in Dalton’s Atomic theory, he proposed a new set of standard symbols for the chemical elements.
Berzelius suggestedjust using letters, argumenting those are easier to write and print.
In 1829, Johann Wolfgang Döbereiner noticed a number of triads of similar elements; so he proposed the known “Law of Triads”(The middle element in the triad had atomic weight that was the average of the other two members and that the densities of some triads followed a similar pattern). Then, other scientists started foundother similarities and differences between triads. They began to arrange the elements in groups.
In 1859, Jean-Baptiste Dumas extended Döbereiner's triads into families of elements in fours.
Thenin 1863, Alexandre-Emile Béguyer de Chancourtois was the first person to notice the periodicity of the elements; similar elements seem to occur at regular intervals when they are ordered by theiratomic weights. He devised an early form of periodic table, which he called the “Telluric Helix”. With the elements arranged in a spiral on a cylinder by order of increasing atomic weight, he saw that...
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