2.2 Merits of Long Form of Periodic Table Over Mendeleef’s Periodic Table

  Periodic Table

    1.0 Introduction
    2.0 Modern Periodic Law & Modern Periodic Table
    3.0 s,p,d,f Block Elements
    4.0 Size and type of bonding in atoms.
    5.0 Ionization Potential
    6.0 Electron Affinity
    7.0 Electronegativity

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2.2 Merits of Long Form of Periodic Table Over Mendeleef’s Periodic Table

• Position of Isotopes & Isobars: Isotopes have same atomic number and the periodic table is based on atomic number. Therefore, various isotopes of the same elements have to be provided the same position in the periodic table. Isobars gave same atomic weights but different atomic numbers and therefore they have to be placed at different positions.
• The position of lanthanides and actinides is more clear now because these have been placed in IIIB groups and due to insufficient space, these are written at the bottom of the periodic table.
• The general electronic configuration of the elements remains same in group.

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Demerits of Long Form of Periodic Table

• The position of hydrogen is still disputable as it was in group $I A$ as well as $IV A$ & $VII A$ in Mendeleef’s periodic table.
• Helium is an inert gas but its configuration is different from that of the other inert gas elements.
• Lanthanide & actinide series could not be adjusted in the main periodic table and therefore they had to be provided with a place separately below the table.