Question

State merits and demerits of mendelevs periodic table

Answer 1

${\purple{\underline{\underline{\huge{\mathtt{Answer:}}}}}}$

Mendeleev's periodic table:

• In Mendeleev's periodic table elements are arranged according to their atomic mass.
• Mendeleev arranged 63 elements on the basis of their atomic mass.
• This periodic table consists of 7 horizontal rows and 8 vertical columns.

Merits of Mendeleev's periodic table:

• Nearly 63 elements were arranged in order of increasing atomic mass upto 7 horizontal rows and 8 vertical columns.
• Each long period was divided into two series, ie even and odd.
• He left blank spaces wo that it could help the scientists ro develop new element.
• When noble gasses were to be discovered he could introduce them in the periodic table without a major change.
• There was gradiation in physical and chemical properties of elements.

Demerits of Mendeleev's periodic table:

• He was not able to locate the position of hydrogen in his periodic table.
• No separate position was given to isotopes.
• Increase in atomic mass was not regular while moving from one element to another, so it could not be predicted how many elements could be discovered between two elements.