In which year did John Alexander Newlands propound a new concept of the 'Law of Octaves' proposing the periodicity of chemical elements arranged in order of atomic weight?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 1865.
In 1865, John Alexander Newlands introduced the Law of Octaves, proposing that when chemical elements were arranged by increasing atomic weight, every eighth element exhibited similar properties, much like the notes in a musical octave. Although his idea was initially met with skepticism, it paved the way for future advancements in the organization of the periodic table.