Question

limitation and demerits of dobernier ,newland ,and mendleev​

Answer 1

Answer:

Demerits of Doberiner's Triads :  Could only identify 3 triads. was not able to prepare triads of all known elements

Demerits of Newland law of octaves:

Only applicable upto Ca(Calcium)

Only contained 56 Elements and he assumed only 56 elements existed in nature and no more elements are going to be discovered

In order to fit all elements he fitted 2 elements in 1 block

Put unlike together like apart

Demerits of Mendleev:

Could not assign specific position to Hydrogen

position of isotope were not certain                        

Answer 2

Answer:

Drawback of Dobereiner's triads:

Drawback of Dobereiner's triads:Dobereiner could identify only three triads. He was not able to prepare triads of all the known elements.

Drawback of Dobereiner's triads:Dobereiner could identify only three triads. He was not able to prepare triads of all the known elements.All the known elements could not be arranged in the form of triads.

Drawback of Dobereiner's triads:Dobereiner could identify only three triads. He was not able to prepare triads of all the known elements.All the known elements could not be arranged in the form of triads.For very low mass or for very high mass elements, the law was not holding good. Take the example of F, Cl, Br.

Drawbacks of Newland's law of octave:

Drawbacks of Newland's law of octave:Newland could arrange elements only up to calcium, out of the total 56 elements known.

Drawbacks of Newland's law of octave:Newland could arrange elements only up to calcium, out of the total 56 elements known.After calcium, every eighth element did not possess properties similar to that of the first.

Drawbacks of Newland's law of octave:Newland could arrange elements only up to calcium, out of the total 56 elements known.After calcium, every eighth element did not possess properties similar to that of the first.Only 56 elements were known at the time of Newlands, but later several elements were discovered.

The demerits of the periodic table given by Mendeleev are :

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.

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.

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.

HOPE THIS WILL HELP✌