Question

X and Y are the two extreme elements of the series which obey Newland's law of octaves. How many elements are there in between X and Y?

Answer 1

Newland gave the law of octaves, which states that: When elements are arranged in an increasing order of atomic mass, every eighth element beginning from any element resembles the first element in its physical and chemical properties. So, there are only 6 elements present in between X and Y.