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9.1. The heat of fusion for the ice-water phase transition is 335kJ/kg at 0C and 1 bar. The density of water is 1g/cm3 at these conditions and that of ice is 0.915g/cm3. Develop an expression for the change of the melting temperature of ice as a function of pressure. Quantitatively explain why ice skates slide along the surface of ice for a 100kg hockey player wearing 10cmx0.1cm blades. Can it get too cold to ice skate? Would it be possible to ice skate on other materials such as solid CO2