In which musical note did Newland put the metals Co and Ni with halogens?

Correct option is B

The correct answer is indeed (b) Do.
· In Newlands' Law of Octaves, Cobalt (Co) and Nickel (Ni) were grouped in the musical note Do along with halogens like Fluorine (F), Chlorine (Cl), and Bromine (Br).
· This placement reflected Newlands' early attempt to organize elements based on their atomic weights and properties.
Key Details:
· Newlands' Classification: Proposed in 1864, this law arranged elements in increasing order of atomic weights, with every eighth element showing similar properties, analogous to the repetition of musical notes.
· Grouping Issue: Cobalt and Nickel, which are transition metals, were incorrectly grouped with non-metal halogens, highlighting the limitations of the Octaves approach before the modern periodic table.