Question

what are the achievements of Mendleev'S PERIODIC table

Answer 1

In 1869, Mendeleev classified the then known 56 elements on the basis of their physical and chemical properties in the increasing order of the atomic masses, in the form of a table. Mendeleev had observed that properties of the elements orderly recur in a cyclic fashion. He found that the elements with similar properties recur at regular intervals when the elements are arranged in the order of their increasing atomic masses. He concluded that 'the physical and chemical properties of the elements are periodic functions of their atomic masses'.

Answer 2

Mendeleev's achievement in periodic table are as follows:-
1. Accommodated noble gases which which were discovered very late.
2. Some gaps were left to accommodate elements to be discovered later
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