Development of the Modern Freezer. Bacteria are usually the cause of food decay, but they can't grow as well or at all in freezing temperatures, which are at 32 degrees Fahrenheit (0 degrees Celsius) or lower.
HF- polar molecule: dipole-dipole forces. There are also dispersion forces and H bond between HF. BF3- nonpolar: dispersion forces. Ar- Dispersion forces between Ar atoms.
Van der Waals force. Van der Waals forces include attraction and repulsions between atoms, molecules, and surfaces, as well as other intermolecular forces. They differ from covalent and ionic bonding in that they are caused by correlations in the fluctuating polarizations of nearby particles (a consequence of quantum dynamics[5]).