Nature of Chemistry

Chemistry is a scientific study on behaviour and properties of matter. It is a science that deals with elements which together make up the compounds which further comprises atoms, molecules and ions. It also deals with their behaviour, composition, properties, structure and the changes that occur in them during a chemical reaction along with other substances.

Chemistry occupies a central position between physics and biology thus it is also known as the “central science” as it provides a base for better understanding of basic and applied scientific knowledge at a fundamental level. 

What Is Chemistry? 

Chemistry helps in addressing topics like atoms and molecules interaction with the help of chemical bonds in order to form new chemical compounds. There are two types of chemical bonds:

• Primary Chemical Bonds: like covalent bonds (in this type of bond atoms share one or more electrons), ionic bonds (in this type atom donates one or more electrons to other atoms in order to produce ions like cations and anions).

• Secondary Chemical Bonds: it includes hydrogen bonds, Van der Waals Force bonds, ion-ion interaction, ion-dipole interaction etc. 

History

The word Chemistry comes from the variation of the word “alchemy” which refers to the early set of practices that surrounds various different elements of chemistry, metallurgy, astrology, astronomy and medicine. The modern version of alchemy comes from the Arabic word al-kimia. Antonie Lavoisier is known as the father of chemistry after the French revolution. He was the one who changed chemistry from a qualitative to a quantitative one. His greatest discovery was that he noted the role of oxygen in the combustion process. He also gave oxygen and hydrogen their name. He was the first to give a list of elements and reconstructed the chemical nomenclature. He exclaimed that matter can change its shape or form but its mass remains constant and never changes. Lavoisier was also the first to discover the existence of silicon. 

Periodic Table

It refers to a tabular arrangement of all elements that are known to man in relation to their increasing atomic number and their changing chemical properties. In this tabular arrangement a row refers to a period and a column refers to a group. Elements are written from left to right and top to bottom in accordance with their increasing atomic number. The first 94 elements have naturally occurred and the rest 95 to 118 are synthesized in the laboratory. The periodic table was given by Dimitri Mendeleev based on the research of other scientists like John Newlands and Antonie Lavoisier. Mendeleev is determined as the father of the Periodic table. Mendeleev’s periodic table is different from the modern one because in Mendeleev’s periodic table the elements are arranged in increasing atomic mass whereas the modern periodic table is based on increasing atomic number.

Periodic Trends 

In the periodic table the properties of chemical elements represent certain specific patterns that are known as periodic trends. These trends are follows:

• Ionization Energy

• Metallic Character

• Atomic Radius

• Electronegativity

• Electron Affinity

• Ionic Radius

• Chemical Reactivity

• Shielding effect

Changes in Periodic Trends

On moving from Left to Right the following properties can be seen:

• Atomic Radius Decreases

• Ionization Energy Increases 

• Electronegativity Increases

• Electron Gain Enthalpy mainly Increases (except for Noble Gas Electrons Affinity is equals to zero).

On moving from Right to Left these following properties are seen:

• Atomic Radius Increases

• Ionization Energy Decreases 

• Electronegativity Decreases

• Electron Gain Enthalpy Decreases

Conclusion

The periodic table has about 118 elements and each element has its specific symbol and atomic number. We can also calculate the atomic mass of each element. Each element is arranged in order of their increasing atomic number. The element possesses a regular repeating chemical and physical properties. In the periodic table the rows are represented by periods or series and columns are represented by groups or families.

In this article we have tried to discuss the trends shown in the periodic table. You will be surprised to know the various facts about chemistry, its origin and history that we have discussed.