Question

What are Intermolecular hydrogen bonding and any one example?

Answer 1

We know that hydrogen bond is defined as an attractive force between partially positive charged atoms with partially negative charged atoms. This is very weak in nature as compared to the strength of covalent bonds. Hydrogen bonds are usually shown as dotted lines between the atoms.

Complete answer: As we know, hydrogen bonding is another most important binding force other than covalent and ionic bonds. Intermolecular forces for example dipole-dipole interactions or hydrogen bonding is one of the important concepts while learning the concept of solvation. A molecule that is polar in nature will form hydrogen bonds with other molecules when they have hydrogen atoms which are further covalently bonded with highly electronegative elements like ammonia in which hydrogen molecules get bonded with nitrogen atoms or hydrogen atoms bonded with each other.
It is another class of attractive forces that arise due to dipole-dipole interaction between a hydrogen atom that is bonded to a highly electronegative atom and another highly electronegative atom while lies in the vicinity of the hydrogen atom. We can take one of the most common examples of hydrogen bonds as those formed in liquid alcohols. Intermolecular hydrogen bonds occur between two separate molecules. They can occur between any numbers of like or unlike molecules as long as hydrogen donors and acceptors are present in positions in which they can interact. For example, Intermolecular hydrogen bonds can occur between ammonia molecules alone, between water molecules alone or between ammonia and water.

Additional Information: Most $OH$ groups make a hydrogen bond to oxygen of an adjacent alcohol, thereby creating a network of hydrogen bonds. In liquid alcohols there is rapid interchange of the hydrogen bonds, with the molecules oriented imperfectly with their neighbors. Thus, we can define hydrogen bonding as a very special class of intermolecular attractive forces that arise only in compounds which have hydrogen atoms bonded to a highly electronegative atom. Hydrogen bonds are mostly strong in comparison to normal dipole-dipole and dispersion forces.

Note:
Remember that Intermolecular forces are those forces which bind the molecules of matter together. Intermolecular forces are higher in case of solid then in liquid and very less in gaseous state. Solid state has definite shape, liquid state takes the shape of the container in which it is kept and gaseous state has no shape.