Q.1. How could the Modern Periodic Table remove various anomalies of Mendeléev’s Periodic Table?
Modern periodic table removes, various anomalies of Mendeleev's periodic table as follows:
(1) In the modern periodic table, elements are arranged in the increasing order of their atomic number, not in the atomic mass.
(2) In the modern periodic table, the isotopes are placed in the same place as they having the same atomic number but different atomic masses.
(3) Now, the same group elements have the same number of valence electrons.
(4) Hydrogen is now placed in the group containing the same valence electrons.