Vanderwaal’s force of attraction:-
Van der Waals forces are weak electrostatic forces that attract neutral molecules to one another. Particles in liquid or air vibrate and move constantly. Thus, they collide with other particles, including the media’s particles such as water molecules—the process known as Brownian motion.
When these neutral particles reach within a threshold distance, electrons from one particle are pulled towards the nucleus of the other particle, thus causing transient polarization (electron-rich domain: δ− and electron-deficient domain: δ+). The δ+ side of one particle attracts the δ− side of another (London dispersion interaction). Particle vibration or motion breaks the interparticle interaction and the particles separate.
Dipole-dipole interavtion:-
Dipole–dipole interactions are weak interactions that arise from the close association of permanent or induced dipoles. Collectively these forces are known as Van der Waals interactions. Proteins contain a large number of these interactions, which vary considerably in strength.
ion-dipole interaction:-
An ion-dipole interaction is the intermolecular force of attraction between a charge ion (cation or anion) and a molecule. It is found commonly in the solution where ionic compounds dissolve in polar solvents. Ion-dipole attractions become stronger as the charge on the ion increases or as the magnitude of the dipole of the polar molecule increases.
Cation is the +ve charged species which can attract the partially negative end of a neutral polar molecule. Anion is the -ve charge species which can attract the partially positive end of a neutral polar molecule. A dipole molecule has a slight charge on either side and that ions have charges, either negative or positive, you can understand how these would bond together. Cations would be attracted to the negative side of a polar molecule, and anions.
Dipole-induced dipole interaction:-
A dipole-induced dipole attraction is a weak attraction that results when a polar molecule induces a dipole in an atom or in a nonpolar molecule by disturbing the arrangement of electrons in the nonpolar species.
Hydrogen bonding:-
Hydrogen bonding is a special type of dipole-dipole attraction between molecules, not a covalent bond to a hydrogen atom. It results from the attractive force between a hydrogen atom covalently bonded to a very electronegative atom such as a N, O, or F atom and another very electronegative atom.
It is of 2 types:-
- Intermolecular hydrogen bonding
- Intramolecular hydrogen bonding
Intermolecular hydrogen bonding:-
When hydrogen bonding takes place between different molecules of the same or different compounds, it is called intermolecular hydrogen bonding.
Intramolecular hydrogen bonding:-
Intramolecular hydrogen bonds are those which occur within one single molecule.
PRESENTED BY-
Banalaxmi Pujhari(Lect. in Chemistry)
