The entropy increases whenever heat flows from a hot object to a cold object. It increases when ice melts, water is heated, water boils, and water evaporates. The change of entropy on melting is a measure of the change in the amount of order in the structure when melting occurs, so depends on chemical structure. When solid is converted liquid, the particles are relatively more free to move and randomness increases. Liquid state has more accessible microstates, so more distribution of energy and hence entropy increases.