Structure of Benzene

Benzene (C6H6) is present in different plants and animals, and the other source of production of benzene is volcanic eruptions and forest fires. Nowadays, benzene is also used in the chemical Industries to make coal and oil. 

Michael Faraday was the person who discovered benzene in the year 1825 by using and illuminating gas. The German Chemist’s name is Eilhardt Mitscherlich heated benzoic acid with lime in 1834. When they start heating both, the best results come out in which benzene is formed. Another German chemist named A.W. von Hofmann isolated benzene from coal tar in 1845. Benzene is also used with many Chemicals to manufacture different products like plastic, detergent, rubber, etc. 

Structure of Benzene

Cyclohexatriene is another name for benzene. Benzene is an organic chemical compound. The general molecular formula of benzene is C6H6. In the Benzene molecule, 6 carbon atoms are attached in a ring of planar form with one atom of hydrogen attached to each carbon atom. 

Benzene only contains carbon and oxygen atoms, so benzene is classified into hydrocarbons. The IUPAC name of benzene is Cyclohexa-1,3,5-triene or 1,3,5-Cyclohexatriene.

X-ray diffraction shows that all six C–C bonds present in benzene are of the same length and the bond length is around 140 picometres (pm). In that case, the carbon Bond length is greater than the double bond and shorter than the single bond, 135 pm and 147 pm, respectively. That distance is because of electron delocalisation. The electrons present in the C=C bond are equally distributed between all the six carbon atoms present in benzene. 

Benzene contains 6 hydrogen atoms from some parent alkane and hexane, with 14. The structure of benzene and chlorhexidine is similar. Still, only the electron delocalisation of the ring and loss of one hydrogen atom from each carbon atom makes a difference in chlorhexidine structure. The molecules are in planar form. 

The molecular orbital involves the formation of 3 electrons to delocalised the π orbital, which spins all six carbon atoms. In structure, the superposition of resonance makes the bonding strong according to valence bonds. It shows that the stability contributes to the peculiar chemical properties and Molecular properties known as aromaticity. 

Due to benzene’s aromaticity, the benzene molecules are in planar form, with a C-C bond length of 1.39 Å and a bond angle of 120°. 

Benzene (C6H6) is the simplest and most organic aromatic hydrocarbon. The colour of benzene appears like a colourless liquid with some odour characteristics. Benzene is also used to produce polystyrene, which is highly toxic and called a carcinogen. 

Resonance of Benzene

In Benzene (C6H6), the oscillating double bond which forms a ring structure was well explained with the help of resonance structure according to the balance bond theory. The atom of carbon present in the benzene ring forms sp2 hybridisation. The two sp2 hybridised orbitals of an atom overlap with the sp2 orbital of an adjacent carbon atom by this 6 carbon-carbon are formed, and another SP2 hybridised orbital which is left combines with orbitals of hydrogen, which is used to form 6 carbon Hydrogen bonds. 

In addition, another orbital, which is an unhybridised p orbital of carbon atoms, will make pi bonds with adjoining carbon atoms by using lateral overlapping. The benzene atom bonds are C1 –C2, C3– C4, C5 – C6 π bonds or C2 – C3, C4– C5, C6-C1 π bonds. This explains the formation of two resonance structures. Kekule explained this structure.

Conclusion

Benzene (C6H6) is an aromatic hydrocarbon. This aromatic hydrocarbon is made up of 6 atoms of carbon and 6 atoms of hydrogen. It is a structure of 6 carbon rings. Michael Faraday was the person who discovered benzene. This aromatic hydrocarbon compound benzene is immiscible in water and soluble in organic solvents. 

The aromatic hydrocarbon has an aromatic odour. The colour of the benzene is a colourless liquid. In addition, the density of water is greater than the density of benzene which is 0.87g cm-3. It has a moderate boiling point of 80.5°C and a high melting point of 5.5°C. This compound shows resonance and is highly flammable.