As per Newlands’ Octaves, which of the following has the same properties as sodium?

As per Newlands’ Octaves, which of the following has the same properties as sodium? Correct Answer Lithium

The correct answer is Lithium.

Key Points

• In 1866, John Newlands, an English scientist, arranged the then-known elements in the order of increasing atomic masses.
• He started with the element having the lowest atomic mass (hydrogen) and ended at thorium which was the 56th element.
• He found that every eighth element had properties similar to that of the first. He compared this to the octaves found in music.
• Therefore, he called it the ‘Law of Octaves’.
• According to the Newlands Octaves, the properties of Lithium and Sodium were found to be the same.

The image shows a demonstration of the arrangement made by Newland.

Additional InformationThere were the following limitations of the Newland's Law of Octaves

• It was found that the Law of Octaves was applicable only up to calcium, as after calcium every eighth element did not possess properties similar to that of the first.
• It was assumed by Newlands that only 56 elements existed in nature and no more elements would be discovered in the future. But, later on, several new elements were discovered, whose properties did not fit into the Law of Octaves.
• After the discovery of the Noble gases, the Law of Octaves became irrelevant. Thus, Newlands’ Law of Octaves worked well with lighter elements only.