Which type of bond is typically weaker and occurs between polar molecules?

The correct answer is hydrogen bond, which is a type of weak non-covalent interaction that occurs primarily between polar molecules. Polar molecules possess regions of partial positive and partial negative charge due to an uneven distribution of electrons. This charge imbalance allows them to interact with other polar molecules through hydrogen bonding.

In a hydrogen bond, a hydrogen atom that is covalently bonded to a more electronegative atom (such as oxygen or nitrogen) is attracted to another electronegative atom from a different molecule. The result is a bond that, while stronger than van der Waals forces, is significantly weaker than covalent or ionic bonds. This characteristic of hydrogen bonds plays a critical role in biological systems, such as maintaining the structure of proteins and the properties of water.

Understanding the nature of hydrogen bonds is essential as they help explain various phenomena in biology, such as the high boiling point of water and the stability of the double helix structure of DNA due to the interaction between complementary bases.