Q.3. What were the criteria used by Mendeléev in creating his Periodic Table?
The criteria used by Mendeleev in creating his periodic table were:
(i) The atomic mass of the elements was used to arrange the elements.
(ii) Grouping the elements according to their similar chemical properties.
And hence proposed that the chemical properties of the elements are the periodic function of their atomic masses and thus he arranged the elements according to the increasing order of atomic masses.