How does heating a substance – to change its state from solid to liquid or liquid to gas (in the latent phases) – increase the potential energy of the system towards zero? Does this mean the potential energy was negative (more negative) and heating it is breaking the attractive forces (which are negative)?
thanks
-yes they were negative converting a system from solid to liquid to gas is like exciting an electron inside an atom where its potential is negative till ionization(free the electron) where its potential reached zero
-the same is for atoms/molecules where the attraction of nucleus to electrons is substituted by intermolecular/atomic attraction forces where the alom/molecule have levels(all have -ve energy) increasing from solid to liquid to gas till reaching zero where these forces are neglected as in the ideal gas