Question

Intramolecular hydrogen bonding is present in

• A.
• B.
• C.
• D. HF

Answer 1

The Correct Option is A

Step 1: Understanding Intramolecular Hydrogen Bonding 

Intramolecular hydrogen bonding occurs when a hydrogen bond forms between a hydrogen atom and an electronegative atom (such as oxygen or nitrogen) within the same molecule, rather than between different molecules.

Step 2: Examining the Given Options

Option (1) and Option (2): These molecules do not exhibit a favorable geometry for intramolecular hydrogen bonding due to their structure. Instead, they are more likely to engage in intermolecular hydrogen bonding.

Option (3): In HF, hydrogen bonding occurs, but it is intermolecular, not intramolecular.

Option (4): The molecule \( C_6H_4NO_2OH \) (hydroxy-nitrobenzene) contains a hydroxy (-OH) group, which can form an intramolecular hydrogen bond with the nitro (-NO₂) group. This leads to a stable structure with intramolecular hydrogen bonding.

Step 3: Conclusion

Thus, the correct answer is:

Option (1)