What were the limitations of Newlands' law of octaves? 

Explanation

Limitations of Newland’s Law of octaves :
It was not applicable through out 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.
Those elements that were discovered after Newland’s octaves did not follow the law of octaves.
The position of cobalt and nickel in the groups of the element (F, Cl) of different properties could not be explained.
Placing of iron far away from cobalt and Nickel, with similar properties as iron could also not be explained.