Question

If a solid line represents a covalent bond and a dotted line represents intermolecular attraction, which of these choices shows a hydrogen bond?

-O...H-C-
-N...H-O-
-C...H-F-
H-H

Answer 1

The correct option that shows a hydrogen bond is -N...H-O-, as it fits the criterion of hydrogen being covalently bonded to a highly electronegative atom (N) and attracted to a lone pair on another electronegative atom (O) in a neighboring molecule.

Step-by-step explanation:

If a solid line represents a covalent bond and a dotted line represents intermolecular attraction, the choice that shows a hydrogen bond is -N...H-O-. This is because hydrogen bonds are a type of dipole-dipole interaction that occurs when a hydrogen atom is covalently bonded to a highly electronegative atom, such as nitrogen (N), oxygen (O), or fluorine (F), and is attracted to a lone pair of electrons on an atom in a neighboring molecule.

Hydrogen bonds are particularly strong among dipole-dipole interactions, although they are much weaker compared to a covalent bond. Therefore, the correct answer is the one where hydrogen is bonded to nitrogen (which is highly electronegative) and is attracted to oxygen from another molecule, hence forming a hydrogen bond.

Answer 2

Generally, a hydrogen bond can be characterized as a proton shared by two lone electron pairs. It occurs when a hydrogen (H) atom, covalently bound to a highly electronegative atom such as nitrogen (N), oxygen (O), or fluorine (F), experiences the electrostatic field of another highly electronegative atom nearby.

Among the choices in the bond (-N...H-O) one side of the Hydrogen is bonded to a highly electronegative atom with a lone pair (-N) and the other side is directly bonded with a highly electronegative atom (O-).

So -N...H-O- shows a hydrogen bond.