न्यूलैंड्स के अष्टक सिद्धांत की क्या सीमाएँ हैं?

Limitations of Newlands’ law of octaves :

$(i)$ It was not applicable throughout the arrangements. It was applicable up to calcium only. The properties of the elements listed after calcium showed no resemblance to the properties of the elements above them.

$(ii)$ Those elements that were discovered after Newlands’ octaves did not follow the law of octaves.

$(iii)$ The position of cobalt and nickel in the group of the elements $(F,\, Cl)$ of different properties could not be explained.

$(iv)$ Placing of iron far away from cobalt and nickel, which have similar properties as iron, could also not be explained.