Final answer:
Hydrogen bonds are weaker than covalent and ionic bonds, with about 21 kJ/mole of dissociation energy, but crucial for the properties of water and biological molecules. Van der Waals interactions are even weaker, but important for the temporary attractions between molecules.
Step-by-step explanation:
In an aqueous solution, the strength of hydrogen bonds and van der Waals interactions plays a crucial role in the behavior of molecules. Hydrogen bonds are relatively weak compared to covalent and ionic bonds, but they are significant enough to influence the physical properties of water. When hydrogen is covalently bonded to highly electronegative atoms like nitrogen (N), oxygen (O), or fluorine (F), these bonds allow for the formation of hydrogen bonds, which have a dissociation energy of about 21 kJ/mole. Van der Waals interactions are even weaker than hydrogen bonds and are the result of transient dipole moments within molecules that induce corresponding dipoles in adjacent molecules, leading to a temporary attraction.
The shape of the water molecule, with its bent molecular geometry, allows for a unique arrangement in ice, where each water molecule forms a lattice structure through hydrogen bonding, leading to ice's lower density compared to liquid water. In biological systems, these weak bonds are critical for stabilizing the structures of DNA and proteins, which are essential for life.