Question

write the merits and demerits of 7 periodic table(3 points )

Answer 1

Advantage of Mendeleev Periodic Table :-
1.He left blank Places which help scientist to discover new element
2.When Noble gasses was discovered Hel could add it to periodic table without any major changle
3.He predicted the property of new element

Disadvantages :-
1. Couldn't explain position of Hydrogen
2.Couldn't answer the question "Can we have an element with atomic mass 3 between Hydrogen and Helium
3 He placed cobalt before Nickel though Cobalt has more mass