Question

what were the two criteria used by Mendeleev in creating his periodic table

Answer 1

1a) Mendeleev’speriodic table was based on the observation that the properties ofelements are a periodic function of their atomic masses. This meansthat if elements are arranged in the increasing order of their atomicmasses, then their properties get repeated after regular intervals.

b)Relative Atomic Mass and similarity of chemical properties
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