If an ice cube melts at 0oc but water also freezes at 0oc, what is the difference between melting and freezing in terms of (a) the energy involved in the phase changes and (b) particles of the substances during the phase changes?

The energy involved in melting in freezing is heat, At 0 degrees Celsius ice is at an equilibrium where the heat energy absorbed during melting (endothermic) and heat energy dispersed during freezing (exothermic). When ice melts its absorbs heat energy to change states, when water freezes to ice it dispersed heat energy so that the particles can move slow enough to be almost frozen, but still very small vibrations throughout the ice. Particles in the frozen state are packed tightly and help together by a crystal lattice and IMF's, liquid is free flowing with free floating particles that can move freely from one another particle. 

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