The weak bonds that are not strong enough to hold atoms together to form molecules but within and around large molecules are called intermolecular forces. These forces include van der Waals forces, hydrogen bonds, and dipole-dipole interactions.

1. Van der Waals Forces:

- Van der Waals forces are the weakest of the intermolecular forces and occur between all molecules.

- They consist of three components:

- London dispersion forces: These are temporary attractive forces that arise due to the fluctuations in electron distribution in molecules.

- Dipole-induced dipole forces: These forces occur when a permanent dipole in one molecule induces a temporary dipole in a neighboring molecule.

- Permanent dipole-permanent dipole forces: These forces occur between molecules with permanent dipoles.

2. Hydrogen Bonds:

- Hydrogen bonds are strong dipole-dipole interactions that occur between a highly electronegative atom (usually F, O, or N) and a hydrogen atom covalently bonded to another highly electronegative atom.

- Hydrogen bonds are stronger than van der Waals forces but weaker than covalent bonds.

3. Dipole-Dipole Interactions:

- Dipole-dipole interactions occur between molecules with permanent dipoles. The positive end of one dipole is attracted to the negative end of another dipole, resulting in a net attractive force.

4. Ionic Interactions:

- Ionic interactions are electrostatic forces between positively charged ions (cations) and negatively charged ions (anions).

- Ionic interactions are stronger than hydrogen bonds and dipole-dipole interactions but weaker than covalent bonds.