Question

What were the criteria used by mendeléev in creating his periodic table? how does the electronic configuration of an atom relate to its position in the modern periodic table?

Answer 1

Mendeleev used atomic masses of the elements to classify them in his periodic table.
Elements with same valency are present in the same group.

Answer 2

Explanation:

In the modern periodic table, atoms with similar electronic configurations are placed in the same column. In a group, the number of valence electrons remains the same.

Elements across a period show an increase in the number of valence electrons.