what are the merits and demerits of modern periodic table.
Merits of Modern Periodic table:
- The "atomic number" has been taken as the basis of classification which is a more fundamental property of elements.
- Since, the classification is based on atomic number, so isotopes (having same atomic no.) are placed at one place which is justified.
- The periodicity in the physical and chemical properties of elements is defined by electronic configuration which explains the nature and behavior of the elements.
- The problem of anomalous pair of elements (as Ar and K) in Mendeleev's table ,is removed as now according to atomic no. Ar(18) is kept before (19).
- The Lanthanides and Actinides of different behavior than d-block elements are placed in different f-block elements at the bottom of the table.
- The table gives a simple and clear view of properties of elements as the elements have clear electronic configurations.
Demerits of Modern Periodic Table:
The Long form of periodic table is demerit free as it has all the qualities what should be in a classification table. However, two main defects could be measured as:
- Position of Hydrogen is ambiguous as it resembles with both the alkali metals and halogen group, but is placed with alkali metals.
- The position of Lanthanides and Actinides are outside the main body which looks inappropriate.