Question

What was Dobereiner’s basis of classification of elements?

Answer 1

So, attempts were made to classify elements on the basis of their atomic masses. ... He grouped the elements with similar chemical properties into clusters of three called 'Triads'. The distinctive feature of a triad was the atomic mass of the middle element

Answer 2

dobereiner's law was that if the elements are written in the form of triads in their increasing atomic weight than the average of first and third atomic weight is equal to the middle atomic weight