Question

write down three major difference between Mendeleev periodic table and Modern Periodic Table

Answer 1

Mendeleev periodic table was based on atomic mass and Modern Periodic Table is based on atomic number .

Answer 2

1.Mendeleev periodic table is based on increasing order of atomic masses. where as modern periodic table is based on increasing order of atomic numbers.
2. Mendeleev periodic table does not shows the proper position of isotopes. whereas periodic table shows proper position of isotopes.
3.mendeleev periodic table has 8 groups whereas modern periodic table has 18 groups.