Various anomalies of Mendeleev’s Periodic Table removed as follows in the Modern Periodic Table: → Elements are arranged in the increasing order of their atomic number in Modern Periodic Table, thus there was no need for keeping more than one element in one slot.
→ In Modern Periodic Table there was no problem of the place of isotopes, as isotopes have same atomic mass with different atomic numbers.
→ Elements having same valence electron are kept in same group.
→ Elements having same number of shells were put under the same period.
→ Position of hydrogen became clarified in as it is kept in the group with the elements of same valence electrons.