Development of Modern Periodic Table

The periodic table refers to an arrangement of the chemical elements that are organized on the basis of their atomic numbers, their electron configurations and their recurring chemical properties. Elements are presented in the periodic table in the order of the increasing atomic number. The standard form of the table contains a grid that has rows called as periods and columns called groups. The history of the periodic table is a reflection of more than two centuries of growth to understand the chemical and physical properties of the elements. The major contributions for the development of the periodic table were made by Antoine-Laurent de Lavoisier, John Newlands, Johann Wolfgang Döbereiner, Julius Lothar Meyer, Glenn T. Seaborg, Dmitri Mendeleev, and many others. In this article, we will learn in detail about the history of the periodic table, who invented the periodic table, and the evolution of the periodic table.

Brief History of Periodic Table

The periodic table is for many people the symbol of chemistry. It is a single image in a tabular form which contains all the known elements in the universe that are combined into an easily readable table. There are many different patterns present in the table as well. All of these elements seem to fit together and connect to each other to form a readable table and, in turn, the image of chemistry. The thought of elements first came around in 3000 B.C. The Greek philosopher Aristotle had an idea that everything on the Earth was made up of these elements. In the ancient times, elements like gold and silver were easily accessible, however, the elements which Aristotle chose were Earth, Water, Fire, and Air.

In 1649 the idea of elements took a big step when Hennig Brand was the first person to discover a new element called phosphorous. Brand was an alchemist who was in search of the Philosopher's Stone, or an object which would turn any kind of ordinary metal into gold. In his search, he had tried everything, including distilling the human urine. When this experiment was carried out Brand discovered a glowing white coloured rock. This was the new element he had decided to call phosphorous. The alchemists and scientists of this enlightenment period added varying amounts of knowledge to several ideas about different elements. In 1869 there were already 63 elements that were discovered. With every new element which was found, scientists began to realize that there were some sorts of patterns that were developing and some started to put these elements into a table.

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Doberiener’s Triads

The German chemist named Johann Dobereiner in the year 1800 first observed that there were similarities in the elements based on their properties. He saw that there were groups that consisted of three elements or triads which have much similar chemical and physical properties.

In every group, the atomic weight of the middle element was noted to be half the sum of the atomic weight of the other two elements of the group. Properties of the middle element also lied in the middle of both the other elements. Dobereiner named this method of grouping as the law of triads. Later on, it was found that this law of triads was not true for each element and hence, it was not proven to be successful.

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Newland’s Octaves

In the year 1865, after the failure of Doberiener’s law of triads, the English chemist John Alexander Newlands introduced the law of octaves. According to him, the elements can be arranged in an ascending order according to their atomic weights. He also admitted that in this arrangement every eighth element in a row had the same properties to that of the first element of the same row, which depicts the octaves of music. This law was also not successful since it was only true for the elements up to calcium.

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Mendeleev’s Periodic Table

The actual development in the periodic table happened after the development of Mendeleev’s periodic table. He introduced a law which stated that the properties of a given element are the periodic function of their atomic masses. He then arranged elements in periods or horizontal rows and groups or vertical columns in the increasing order according to their atomic weights. The vertical column contains the elements which have similar properties.

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Limitations of Mendeleev’s Periodic Table

The following are the limitations of the Mendeleev’s periodic table.

  1. The periodic table did not provide a clear idea of the structure of the atom.

  2. For arranging the elements in a group, the order of atomic weight was reversed many times.

FAQ (Frequently Asked Questions)

1. Who Discovered the Periodic Table?

In the year 1869, a Russian chemist Dimitri Mendeleev started to develop the periodic table by arranging the chemical elements by atomic mass. He predicted the discovery of several other elements and left spaces open in his periodic table for them to accommodate. He is the one who invented the first periodic table and is the periodic table founder.

3. Who Discovered Modern Periodic Table?

If you look at the periodic table discovery, Dmitri Mendeleev is known as the father of the periodic table. However, as the development of the periodic table was gradually done, the modern periodic table was discovered by Henry Moseley.