Question

what are the demerits of Mendeleev periodic table​

Answer 1

we can't fix the position of hydrogen in his table

Answer 2

Answer:

The demerits of the periodic table given by Mendeleev are :

He could not place the element Hydrogen in appropriate position in the periodic tabular form.

There was no regular trend in increasing of atomic mass when moved along the elements.

More elements was yet to be known.

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