Question

What are the two drawbacks of mandeleeve what are the two drawbacks of modern periodic table​

Answer 1

• In Mendeleev's periodic table there were gaps for undiscovered elements. Modern periodic table maintains uniformity.
• In Mendeleev's periodic table noble gases were not placed (as they are not discovered at that time).
• In Modern periodic table noble gases in a seperate group named as group-18.

Answer 2

Answer:

position of hydrogen: hydrogen is placed in group I.

Anomalous pairs: in certain pairs of elements, the increasing order of atomic masses was not obeyed.

position of isotopes: isotopes are atoms of the same element having different atomic masses but same atomic number.

Explanation:

hope it helps you☺☺

flw me☺

please mark as brainlist❣