In 1866, John Newlands, an English scientist, arranged the then known elements in the order of __________. It is known as 'Newlands' Law of Octaves'.

Correct option is C

The correct answer is (c) Increasing atomic masses.
· In 1866, John Newlands, an English scientist, arranged the known chemical elements in the order of their increasing atomic masses. This arrangement is famously known as Newlands' Law of Octaves. He observed that every eighth element shared similar properties, akin to the octaves in music, where every eighth note is similar.
Information Booster:
· Law of Octaves: Newlands’ Law of Octaves was one of the earliest attempts to classify elements systematically. However, it had limitations, as it only worked well for lighter elements and failed to account for the properties of heavier elements.
· Importance: Despite its limitations, Newlands' work was an important step towards the development of the modern periodic table, which Dmitri Mendeleev later refined.