Which answer describes hydrogen bonding?
responses
a. the attraction between hydrogen and the permanent dipole of a weakly electronegative molecule.
b. the attraction between hydrogen and lone electron pairs of a strongly electronegative molecule.
c. the attraction between hydrogen and an induced dipole of a strongly electronegative molecule.
d. the attraction between hydrogen and a permanent dipole of a weakly electronegative molecule.
The Correct Answer and Explanation is :
The correct answer is b. the attraction between hydrogen and lone electron pairs of a strongly electronegative molecule.
Explanation:
Hydrogen bonding is a specific type of intermolecular force that occurs when a hydrogen atom is covalently bonded to a highly electronegative atom, such as nitrogen (N), oxygen (O), or fluorine (F). This electronegative atom pulls electron density away from the hydrogen atom, creating a dipole where the hydrogen end is slightly positive (δ+) and the electronegative atom is slightly negative (δ-).
The key feature of hydrogen bonding is the strong attraction that occurs between the hydrogen atom of one molecule and the lone electron pairs of the electronegative atom in another molecule. For instance, in water (H₂O), the hydrogen atoms form bonds with oxygen, which is highly electronegative. This leads to the formation of a partial positive charge on the hydrogen atoms. When two water molecules come close, the slightly positive hydrogen atom of one molecule is attracted to the lone pairs of electrons on the oxygen atom of another molecule, resulting in a hydrogen bond.
Hydrogen bonds are crucial for many biological and chemical processes. For example, they contribute to the unique properties of water, such as its high surface tension, boiling point, and solvent capabilities. In biological systems, hydrogen bonds are fundamental in maintaining the structure of proteins and nucleic acids like DNA. The specific pairing of bases in DNA relies on hydrogen bonds, ensuring the stability of the double helix structure.
Overall, hydrogen bonding significantly influences molecular interactions and the physical properties of substances, making it a vital concept in chemistry and biology.