Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A) : Benzene is more stable than hypothetical cyclohexatriene
Reason (R) : The delocalised π-electrons cloud is attracted more strongly by the nuclei of the carbon atoms than the electron cloud localised between two carbon atoms.
In the light of the above statements, choose the correct answer from the options given below
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A) : Benzene is more stable than hypothetical cyclohexatriene
Reason (R) : The delocalised π-electrons cloud is attracted more strongly by the nuclei of the carbon atoms than the electron cloud localised between two carbon atoms.
In the light of the above statements, choose the correct answer from the options given below
Show Hint
Resonance stabilization and delocalization of π electrons provide benzene with extra stability compared to hypothetical cyclohexatriene.
Both (A) and (R) are true but (R) is not the true explanation of (A)
(A) is false but (R) is true
(A) is true but (R) is false
Both (A) and (R) are true and (R) is the true explanation of (A)
The Correct Option is D
Solution and Explanation
Assertion (A): Benzene is more stable than hypothetical cyclohexatriene because of resonance stabilization. The delocalization of π electrons in benzene creates extra stability compared to isolated double bonds in cyclohexatriene.
Reason (R): The delocalized π electron cloud in benzene forms a bonding molecular orbital (BMO), which is strongly attracted by the nuclei of the carbon atoms, resulting in additional stabilization.
Since the reason explains the assertion, both A and R are correct, and R is the correct explanation of A.
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Concepts Used:
Hydrocarbons
Hydrocarbons can be described as organic compounds that consists only hydrogen and carbon atoms. These compounds are of different types and thereby have distinct natures. Hydrocarbons are colorless gases and are known for discharging faint odours. These have been categorized under four major classes named as alkynes, alkanes, alkenes, and aromatic hydrocarbons.
Types of Hydrocarbons
- Saturated hydrocarbons - Saturated hydrocarbons are those compounds where there is a single bond exists between carbon atoms and are saturated with atoms of hydrogen.
- Unsaturated hydrocarbons - Hydrocarbons comprises of at least one double or triple bond between carbon atoms are known as unsaturated hydrocarbons.
- Aliphatic hydrocarbons - The term denotes the hydrocarbons formed as an outcome of the chemical degradation of fats. Aliphatic hydrocarbons are basically chemical compounds.
- Aromatic hydrocarbons - They are distinguished because of the presence of benzene rings in them. They give away distinct types of aroma. These hydrocarbons comprises of only hydrogen and carbon atoms.