Humber Admissions Practice Test

What type of attraction is described by hydrogen bonds?

1. Strong attraction between ions

2. Weak attraction between a hydrogen atom and another atom

3. Strong covalent bonds

4. Repulsive interactions between atoms

The correct answer is: Weak attraction between a hydrogen atom and another atom

Hydrogen bonds are characterized as a weak attraction between a hydrogen atom and another atom that carries a partial negative charge, often an electronegative atom such as oxygen, nitrogen, or fluorine. This type of attraction occurs because the hydrogen atom, when covalently bonded to an electronegative atom, takes on a slight positive charge due to the difference in electronegativity. This results in an attraction to another electronegative atom’s lone pair of electrons, creating the hydrogen bond. The nature of hydrogen bonds is crucial in many biological and chemical processes, such as the structure of water and the properties of DNA. Their relatively weak nature compared to covalent or ionic bonds allows for flexibility in molecular structures, which plays a significant role in the function of proteins and nucleic acids. In contrast, other options describe different types of interactions that do not capture the essence of hydrogen bonding. For example, strong attractions between ions refer to ionic bonds, which involve a complete transfer of electrons rather than partial charges. Strong covalent bonds involve the sharing of electrons between atoms, and repulsive interactions occur at very short distances when electronic clouds of atoms begin to overlap, causing atoms to push away from each other. None of these accurately depict the nature of hydrogen