What is understood by hydrogen bonding? How does hydrogen bonding? How does hydrogen bonding affect the properties of compounds? How many types of hydrogen bonding are there?
A hydrogen bond is the electrostatic attraction between polar groups that occurs when a hydrogen (H) atom bound to a highly electronegative atom such as nitrogen (N), oxygen (O) or fluorine (F). Its energy is in range between 5 and 30 kJ/mole, this makes it stronger that van der Waals interaction, but weaker than covalent or ionic bonds.
Hydrogen bonds are created as a form of electrostatic interaction, with its effect amplified by small radius of H atom, which allow creation of effective dipole parts.
Hydrogen bonds manifests in stronger intramolecular interaction, which lead, for example, to higher boiling point of compounds with hydrogen bond in comparison to similar compounds without it. The most popular example – water. Also HB can effect dramatically geometry of the molecules, for example – structure of DNA and proteins is determined by HB, among other factors.
Hydrogen bonds are divided into 2 main categories – intramolecular and intermolecular, depending if H atom and polar atom belong to the one or different molecules.