A refrigerant is a substance or mixture, usually a fluid, used in a heat pump and refrigeration cycle.In most cycles it undergoes phase transitions from a liquid to a gas and back again.Many working fluids have been used for such purposes. R-401A is a HCFC zeotropic blend of R-22, R-152a, and R-124. 2  It is designed as a replacement for R-12. 3  R-404A is a HFC nearly azeotropic  blend of 52 wt.% R-143a, 44 wt.% R-125, and 4 wt.% R-134a. 4  It is designed as a replacement of R-22 and R-502 CFC.
The temperature of the ice will continue to decrease until it reaches the same temperature as the outside air which is 20 F. Liquid water has more energy than frozen water. When water freezes it gives up some of the water's energy. This energy that is given up is the latent heat of freezing.
Then, the heat added does not change the temperature. That heat energy is instead used to break intermolecular bonds and convert ice into water. At this point, there is a mixture of both ice and water. Once all ice has been melted, the temperature again rises linearly with heat added.hese amounts of energy are the molar heat of vaporization and molar heat of fusion. If that amount of energy is added to a mole of that substance at boiling or freezing point, all of it will melt or boil, but the temperature won't change.