Question

State achievement of Mendeleev's periodic table.

Answer 1

Merits of Mendeleev's periodic table are given as follows.

1. Grouping of elements: He generalized the study of elements known to a study of mere eight groups.
2. Left gap for undiscovered elements: Mendeleev's left some gaps in the periodic table for the elements not known then. He correctly thought that such elements would be discovered later.
3. Prediction of properties of undiscovered elements: He predicted the properties of undiscovered elements on the basis of the properties of elements lying adjacent to the vacant slots.
4. Corrected incorrect atomic mass: He corrected the value of the atomic mass of elements like gold and platinum by placing them on the basis of similarities in their properties.