Periodic Table and Periodicity of Properties
In 19th century, (before 1869) many pseudoscientific arrangement of elements were proposed. But none withstood the test of time and so were rejected. During 1869, first of all, Mendeleev (Russian chemist) realized that atomic weights of elements are related with their properties. On this observation, he proposed a law for the arrangement of elements.
MENDELEEV’S PERIODIC LAW
This law states that properties of elements and their compounds are the periodic function of their atomic weights. He, then arranged the elements in increasing order of their atomic weights. It resulted into a tabular form, so it is called Mendeleev’s periodic table. Only 63 elements were known when this classification was presented. ...