Historical development of the periodic table

We now know more than 100 elements, the elements were classified as metals, metalloids and non metals. Metals are good conductors of heat and electricity, they are shining and they are malleable and ductile. It would be difficult to study individually the chemistry of all the elements and their numerous compounds. The periodic table provides a systematic and extremely useful framework for organizing a lot of information available on the chemical behavior of the elements into a few simple and logical patterns. This gave rise to the necessity of classifying the elements into various groups or families having similar properties.

Introduction to the historical development of the periodic table 

There were many chemists who has contributed their theories for the historical development of periodic table.  Some of them are:
Dobereiner’s Triads
Lother-Meyer’s Arrangement
Newlands Law of Octaves

Dobereiner’s Triads contribution for the historical development of periodic table

In 1829, John Dobereiner (German Chemist) classified elements having similar properties into groups of three. These groups were called triads. According to this law when elements are arranged in the order of increasing atomic mass in a triad, the atomic mass of the middle element was found to be approximately equal to the arithmetic mean of the other two elements. For example lithium, sodium and potassium constituted one triad. However, only a limited number of elements could be grouped into traids.

Newlands Law of Octaves contribution for the historical development of periodic table
In 1865, John Newlands (English Chemist) observed that if the elements were arranged in order of their increasing atomic weights, the eighth element starting from a given one, possessed properties similar to the first, like the eighth note in an octave of music. He called it the law of octaves. It worked well for the lighter elements but failed when applied to heavier elements.

Lother-Meyer’s Arrangement contribution for the historical development of periodic table

In 1869, J. Lother-Meyer in Germany gave a more detailed and accurate relationship among the elements. Lother-Meyer plotted atomic volumes versus atomic weights of elements and obtained a curve. He pointed out that elements occupying similar positions in the curve possessed similar properties.