Question

Why Dobereiner, Newlands and Mendeleeff were not 100% successful in their classification of elements ? Why the modern table is relatively a better classification ? Predict the reason.

Answer 1

Dobereiner, Newlands and Mendeleeff were not 100% successful in their classification of elements because they were trying to classify the elements based on the atomic mass of the element. But not the atomic mass, atomic number of the element is the fundamental quantity so they all failed. Modern table was successful as the classification was done on the based of atomic number.