Question

merits and demerits Mendeleev's periodic table​

Answer 1

Merits are as follows:-

 1. There was a regular gradation in physical and chemical properties of elements.

 2. The group number of an element indicates highest oxidation state that it can attain.

 3. There were many vacant spaces in Mendeleev's periodic table for the elements to be discovered. He  named them Eka-Boron, Eka-Aluminium and Eka-silicone He also predicted the properties of these  undiscovered elements including atomic masses. These elements were discovered as Sc ,Ga and Ge  with same features as he predicted.

 4. Mendeleev’s arrangement helped to correct atomic masses of a number of elements.

Demerits are as follows:-

 1. The elements, if arranged according to their atomic weights show an evident periodicity of  properties. 

 2. Elements which are similar as regards their chemical properties have atomic weights which are either  nearly the same value or which increase regularly. 

 3. The arrangement of the elements or of groups of elements in the order of their atomic weights,  corresponds with their so called valencies. 

Answer 2

this is your answer,

merits and demerits of Mendeleev's periodic table.