Question

what was Mendeleev basis for classification of element's ?

Answer 1

Atomic mass was the basis for classification of periodic table.

Answer 2

Mendeleev in 1869 classified the 56 elements.

This classification is based on physical and chemical properties.

Another basis is upon atomic masses. The elements are arranged in increasing order of the atomic masses.

This arrangement is a tabular arrangement and is also called as periodic table.

Mendeleev also observed that the chemical and physical properties occur in a cyclic manner.