What does breaking or overcoming intermolecular forces mean?

Question

Latent heat is thermal energy that rather than increasing the temperature or the kinetic energy of a substance is used to break intermolecular forces. It is also defined as overcoming intermolecular forces. The latter definition seems inaccurate to me since overcoming implies that a molecule has enough energy that it cant be bound by the intermolecular forces, and that crossing a temperature threshold means 'overcoming' or not being affected by the intermolecular forces, which suggest that temperature still increased.

We say energy is used to break intermolecular forces so the temperature doesnt increase. My question is when we say break what do we even mean? Intermolecular forces are due to the variable poles of molecules. It is some sort of attraction. Isnt attraction overcomed? That there is a point where a susbtance has enough energy that the attraction doesnt have any affect in it. This contradicts the latent heat, which implies some chain has to be broken.

Answer 1

This contradicts the latent heat, which implies some chain has to be broken.

If you think of intermolecular bonds as "chains", you are wrong, and it is clear that this is where your confusion lies.

There is no such thing as chains binding molecules together that can be broken. The forces binding molecules, like electric and magnetic forces, act over a distance and fall off with distance; there is region whereby these forces are strong enough that the molecules do not fly apart, whereas another region whereby these forces are weakened enough that the molecules no longer get bound together, thus flying apart.

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Temperature is a measure of the average kinetic energy of particles. Heat is a form of energy, and when we heat a pure substance across either the melting point or boiling point, we observe that, over some region, the heating does not cause an increase in temperature. This means that the heating, all that energy being input to the substance, had gone into increasing the potential energy of the particles and nowhere else. The potential energy of the particles have increased because it takes energy to pull molecules apart, due to the intermolecular forces trying to pull them together.