When the following substances go from liquid to solid, which would require the lowest temperature for it to freeze? Ar, C6H12, HF, NaCI, Cu Why?...

The freezing point of a substance is related to the intermolecular forces that exist between the particles of a substance.

Intermolecular forces are the forces of attraction or repulsion that act between the particles of a substance. A particle can be composed of atoms, molecules, or ions. 

The different types of intermolecular forces are listed below from strongest to weakest:

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  Electrostatic forces: strong attraction between oppositely charged particles


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  Hydrogen bonding forces: attraction between the H atom of one molecule and the F, O, or N atom of another molecule


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  Dipole-dipole forces: attraction between polar molecules with an uneven charge distribution


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  London dispersion forces: attraction between nonpolar molecules 

The stronger the forces between the particles, the higher the freezing point. Therefore, the substance with the weakest intermolecular forces will have the lowest freezing point. The substance with the weakest intermolecular forces (London dispersion forces) and the lowest freezing point is argon (Ar).