(a) Did Dobereiner’s triads also exist in the columns of Newlands’ law of octaves? Explain your answer. (b) What were the limitations of Dobereiner’s classification of elements?
(a) Did Dobereiner’s triads also exist in the columns of Newlands’ law of octaves? Explain your answer. (b) What were the limitations of Dobereiner’s classification of elements?

(a) Yes, Dobereiner’s triads also exist in the columns of Newlands’ Octaves. This can be explained by taking the second column of the Newland’s classification of elements which has the elements lithium, sodium and potassium that form a Dobereiner’s triad.

(b) The main limitation of Dobereiner’s classification of elements was that it failed to arrange all the known elements by that time in the form of triads of elements having similar chemical properties. It also failed to explain the relation between atomic masses of elements and their chemical properties.