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.
The intermolecular forces of attraction considered here are: Van der Waals' forces; permanent dipole-permanent dipole interactions; hydrogen bonding; Van der Waals' forces. Van der Waals' forces are forces of attraction which exist between all atoms and molecules. Van der Waals' forces are much weaker than all other types of bonding. They are only significant in atoms and molecules which have no other types of intermolecular forces of attraction, for example, discrete non-polar molecules and the Group 0 elements.