Question

What is your observation from Newland’s octaves?

Answer 1

An English scientist called John Newlands put forwardhis law of octaves in 1864. He arranged all the elements known at the time into a table in order of relative atomic mass. ... For example, starting at Li, Be is the second element, B is the third and Na is theeighth element.

Answer 2

See the attached image (Created by me)

Newlands’ Octave : John Newlands arranged the elements in order of their increasing atomic mass.

It states that whenever the elements are arranged in increasing order of their atomic mass, the properties of the eighth element are a kind of repetition of the first, just like the notes of music.

Limitations of Newlands’ law of octaves :

(1) The law was applicable to elements upto calcium (Ca) only.

(2) It contained only 56 elements. Further it was assumed by Newlands that only 56 elements existed  in nature and no more elements are going to be discovered in the future.

(3) In order to fit these elements into the table, Newlands adjusted two elements in the same slot and  also put some unlike elements under the same note.

For example, cobalt and nickel are in the same  slot and these are placed in the same column as fluorine, chlorine and bromine which have very  different properties than these elements.

Iron, which resembles cobalt and nickel in properties, has  been placed differently away from these elements.