what are merit&demerit of Mendeleev periodic table
Answers
Merits of Mendeleev Periodic Table
Some gaps were left for the elements yet to be discovered. Thus, if a certain new element is discovered, it can be placed in a new group without disturbing any existing group.
Demerits of Mendeleev Periodic Table
He was unable to locate hydrogen in the periodic table.
Increase in atomic mass was not regular while moving from one element to another. Hence, the number of elements yet to be discovered was not predictable.
Later on, isotopes of elements were found which violated Mendeleev’s periodic law.
In 1869, after the rejection of Newlands Octave Law, Mendeleev Periodic table came into the picture. In Mendeleev's periodic table, elements were arranged on the basis of the fundamental property, atomic mass, and chemical properties. During Mendeleev's work, only 63 elements were known.
