John Newlands (1 janv. 1865 – 1 janv. 1865)

Description:

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Introduction and Basis:
John Newlands was a British chemist who published his Law of Octaves in 1865. By this time, 47 elements had already been discovered. He arranged all the elements based on their atomic masses in an increasing order. He found that every eighth element had properties similar to that of the first. He compared this to the octaves found in music and therefore, this classification was known as Newlands Octaves.

Examples:
For example, the first element of his table was H (Hydrogen), and the eighth element was F (Fluorine). He found that they had similar properties as every eighth element had properties similar to that of the first.

Limitations and Comparisons:
However, like the two previous theories, this classification had its own share of shortcomings, the main point being that Newland could arrange elements only up to calcium out of the total elements known. The remaining elements after calcium did not show similar properties. Later on, several new elements which were not included in Newlands classification were discovered, yet it did not allow space for undiscovered elements. It also had two elements in one box. So, Newlands Octaves was criticized and did not gain recognition.

Compared to Lothar Meyer's periodic table, Newlands' Law of Octaves was simpler and less comprehensive. However, Meyer's table was more accurate and better able to predict the properties of undiscovered elements.
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