Question

[TBQ.VI.(3)]
What are the limitations of Mendeleev’s periodic table?

Answer 1

Limitations of Mendeleev’s periodic table:

• Elements with large difference in properties were included in the same group. Eg: Hard metals like copper (Cu) and silver (Ag) were included along with soft metals like sodium (Na) and potassium (K).
• No proper position could be given to the element hydrogen. Non-metallic hydrogen was placed along with metals like lithium (Li), sodium (Na) and potassium (K).
• The increasing order of atomic mass was not strictly followed throughout. Eg. Co & Ni, Te & I.
• No place for isotopes in the periodic table.