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Present Form of the Periodic Table

This article talks about the present form of the periodic table, periodic table of elements and the trends of the modern periodic table in detail.

The popularity of the modern periodic table comes from it being an easy-to-use reference. This table has simplified the study of chemistry. By memorizing the periodic table of elements, you can trace their physical and chemical properties. Predictions regarding the compounds formed by an element are determined based on its position in the table.

Present Form of the Periodic Table

A periodic table of elements uses a tabular format to represent discovered chemical elements. In this table, elements are placed under rows (periods) and columns (groups) in the increasing order of their atomic numbers.

Russian chemist and inventor Dmitri Mendeleev published the first version of the modern periodic table in 1869. The periodic table has evolved to reflect decades of scientific development in chemistry and physics. As of date, the most significant achievement in science is the modern periodic table. This table consists of 18 vertical columns, seven horizontal rows, and 118 elements.

What are the Periodic Trends of the Modern Periodic Table?

Specific patterns in the periodic table that illustrate different aspects of an element are the ambit of periodic trends. It includes the element’s size and electronic properties. These trends result from similar atomic structures between elements and their periodic nature.

Let us now introduce the periodic trends of the periodic table:

· Electronegativity Trends:

A chemical property of an atom that describes its ability to attract and bind with electrons is defined as electronegativity. However, there is no standard method for calculating electronegativity because of its qualitative properties.

The tendency of an atom of a given chemical element to attract shared electrons in the process of forming a chemical bond, is what defines electronegativity. Linus Pauling introduced the concept of electronegativity in 1932. The Pauling scale explains the relationship between energy of a bond and electronegativity.

Across a period from left to right, the electronegativity increases. However, contrary to this, the same decreases as you move down a group. The former happens because the nuclear charge increases rapidly compared to the electron shielding when moving from left to right.

· Electron Affinity Trends:

The ability of an atom to accept an electron by a neutral atom in gaseous phase is what can be defined as electron affinity. 

Electron Affinity of an atom or molecule has to do with the amount of energy released every time an electron is attached to a neutral atom or molecule in the gaseous state leading to formation of an anion.

The more negative is the electron affinity value, the higher is an atom’s affinity for electrons. Electron Affinity can be measured quantitatively to mark the energy change that occurs when an electron is added to a neutral gas atom.

You must know that electron affinity will increase from left to right on a periodic table. 

The decrease in the atomic radius causes this. Likewise, electron affinity decreases from top to bottom within a group. Again, this is a result of the increase in the atomic radius.

· Ionization Energy Trends:

Ionization energy trends relate to the energy required to remove an electron from an isolated atom or molecules. As you move down the group, ionization energy decreases. This happens because of electron shielding. However, ionization energy increases when you move left to the right on a periodic table. This is a result of valence shell stability. 

Noble gases possess complete valence shells. A direct result of this is them holding high ionization energies. Considering all the elements on the periodic table, the one with the highest ionization energy is helium.

· Atomic Radius Trends:

One-half of the distance between the nuclei of two atoms is what the atomic radius is all about. However, the complexity comes into play because not all atoms are bound together in the same way.

Atomic radius decreases from left to right in the period. It is because of the rise in the number of protons and electrons across a period. Protons have a greater effect than electrons. The result is electrons being pulled to the nucleus, which results in a smaller radius.

On the other hand, atomic radius increases from top to bottom in a group. 

·Melting Point Trends:

The Melting Point of an element could be explained as the energy required to change the element’s state from solid to liquid. Herefore, the stronger the bond between the atoms, the higher will be the melting point.

Since melting points are varied, they do not form a distinguishable trend across the periodic table. However, a peculiar pattern can be observed.

In the case of metals, a high melting point is projected. Non-metals possess lower melting points. We know that there is an exception in every case.

Carbon, a non-metal, possesses the highest melting point of all the elements. In addition, semi-metal boron has a high melting point.

· Metallic Character Trends:

The metallic character of an element has to do with the readiness of an atom to lose an electron. From left to right across a period, the metallic characteristics decrease. This is due to a decrease in the atom’s radius, which allows the outer electrons to ionize more readily.

Likewise, metallic characteristics increase down the group. The atomic radius increases due to electronic shielding. The metallic character has to do with the ability to lose electrons. Contrary to this, non-metallic-character relates to the ability to gain electrons.

 Conclusion:

The popularity of the modern periodic table comes from it being an easy-to-use reference. This table has simplified the study of chemistry. By memorizing the periodic table of elements, you can trace their physical and chemical properties. Predictions regarding the compounds formed by an element are determined based on its position in the table.

This table acts as a rich source of information. Additionally, it highlights details about the relation between different elements.

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