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Periodic Table

Last updated date: 28th Feb 2024
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What is Periodic Table?

The periodic table is an organised list of all chemical elements in order of increasing atomic number—that is, the total number of protons in the atomic nucleus. When chemical elements are grouped in this way, their properties follow a recurring pattern known as the "periodic law," in which elements in the same column (group or periodic table groups) exhibit similar properties. Dmitry I. Mendeleyev's first discovery, achieved in the mid-19th century, has been invaluable to the development of chemistry.

The most reactive element in periodic table is Fluorine. Let us understand what is periodic table and more details associated with it from this article.

Overview of the Periodic Table

The order of elements in the periodic system is determined by their atomic numbers, the integers of which are equal to the positive electrical charges of the atomic nuclei represented in electronic units. This was not realised until the second decade of the 20th century. In the years since, researchers have made significant progress in explaining the periodic law in terms of atoms and molecules' electrical structure.

This clarification has increased the law's worth, and it is still in use now as much as it was at the turn of the 20th century, when it expressed the only known link between the elements. The modern periodic table is also referred to as the dynamic periodic table or the periodic table with atomic mass.

The periodic table of elements chart is represented below. Students can also avail the periodic table pdf from this article.

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History of the Periodic Law

Analytical chemistry—the art of distinguishing between different chemical substances—underwent rapid development in the early 19th century, resulting in the accumulation of a substantial body of knowledge about the chemical and physical properties of both elements and compounds. This rapid expansion of chemical knowledge necessitated categorization, because not only the formalised literature of chemistry, but also the laboratory arts by which chemistry is passed down as a living science from one generation of chemists, are based on classification.

Relationships were more easily detected among compounds than among elements, resulting in an element classification that was several years behind that of compounds. In fact, even half a century after the systems of classification of compounds became widely used, chemists couldn't agree on how to classify elements.

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J.W. Döbereiner discovered that strontium's combining weight, or atomic weight, is midway between that of calcium and barium in 1817, and that other "triads" exist a few years later (bromine, iodine (halogens), lithium, potassium (alkali metals) sodium, and chlorin).

Between 1827 and 1858, J.-B.-A. Dumas, L. Gmelin, E. Lenssen, Max von Pettenkofer, and J.P. Cooke improved on Döbereiner's ideas. Fluorine was added to the halogens, and magnesium was added to the alkaline-earth metals, showing that similar relationships extended beyond the triads of elements. One family includes oxygen, sulphur, selenium, and tellurium, while another includes nitrogen, phosphorus, arsenic, antimony, and bismuth.

Later, attempts were made to show that the atomic weights Later, attempts were made to demonstrate that the atomic weights of the elements could be stated by an arithmetic function, and in 1862, A.-E.-B. de Chancourtois suggested an element classification based on Stanislao Cannizzaro's 1858 system's new atomic weight values.

He proposed that "the properties of the periodic table of elements are the properties of numbers" as a result of the helical curve, which moved closely related elements into corresponding points above or below one another on the cylinder, a stunning prediction in light of present knowledge.

Structure of Periodic Table

The periodic table's structure is highly important. The current table contains 117 elements in a very specific order in order to show chemical characteristic similarities and contrasts. Only 94 elements are found in nature, while the remaining 24 were created using particle accelerators.

A black stair-step line divides the metal and non-metal elements in most copies of the periodic table. Metals are on the left, whereas non-metals are on the right. In addition, elements are placed in increasing atomic number order, which relates to the amount of protons in each atom's nucleus.

The rows are also arranged in such a way that objects with similar properties are grouped together in the same column. The symbol, atomic number, atomic mass, electronegativity, electron configuration, and valence numbers are all included in each element square. The lanthanoids and actinides are found in a two-row block of elements at the bottom of the periodic table. Inner transitional metals are the name given to this group of metals or ​​periodic table groups.

A few of the periodic table elements list is tabulated below.

Periodic Table Elements List

Element Name


Atomic Number










Fluorine is the most reactive element in the periodic table.

Classification of the Periodic Table of Elements

J.A.R. Newlands proposed classifying the elements in order of increasing atomic weights in 1864, allocating ordinal numbers from unity upward to the elements and categorising them into seven groups or the periodic table groups with qualities similar to the first seven elements discovered at the time: hydrogen, lithium, beryllium, boron, carbon, nitrogen, and oxygen. By similarity with the seven intervals of the musical scale, this relationship was named the law of octaves.

Mendeleyev proposed the periodic law in 1869, which states that "the elements arranged according to the magnitude of atomic weights show a periodic change of properties," as a result of a significant correlation of the properties of the elements and their atomic weights, with a focus on valency (that is, the number of single bonds the element can form). After Mendeleyev's study was published, Lothar Meyer came to a similar result on his own, which he revealed after Mendeleyev's study was published.

The First Periodic Table of Elements

Mendeleyev's 1869 periodic table had 17 columns, with two nearly complete periods (sequences) of elements, from potassium to bromine and rubidium to iodine, followed by two partial periods of seven elements each (lithium to fluorine and sodium to chlorine), and three incomplete periods. Mendeleyev offered a revised 17-group table in an 1871 paper, with the main improvement being the right placing of 17 elements. Students can also get the periodic table pdf.

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Did You Know?

There are other versions of the periodic table. Let us discuss them here.

Alternative long periodic table forms have been proposed. One of the first, described by A. Werner in 1905, divides each of the shorter periods into two portions, one at either end of the table, covering the elements in the longer periods that they most resemble. The Bayley-type table's many tie lines connecting the periods are therefore removed. The lanthanoid and actinoid elements can be moved to a separate region to greatly improve this type of table. This variant of the table had become the most popular by the mid-20th century.

FAQs on Periodic Table

1. Give the Importance of the Periodic Table?

Answer: It is the basis of all chemistry fundamentals. Because chemistry covers our environment, the fundamentals of everything are now dependent on it. Give it a chance and reconsider if someone has trouble accepting that everything around us is chemistry. Consider anything concrete that does not involve chemistry. Impossible. Starting with the air you breathe and ending with the ashes you become after cremation, everything concrete has a chemical makeup and, as a result, chemistry is involved.

2. Give the Uses of the Periodic Table?

Answer: Periodic table is used To study the elements of having all of the elements at one spot (easily accessible), Predicting the properties of undiscovered elements, to determine the number of electrons, protons, and neutrons in a given chemical, and so on.