Answer:
Explanation:
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1. When a solid substance is heated, its temperature will rise until it reaches a critical temperature. At this point, the item won’t melt unless more heat is provided. This additional heat represents energy needed to change the state of the substance from solid to liquid. This energy loosens the ties of molecules, causing them to move faster. When enough heat energy is provided, the substance will change to the liquid state, but the temperature of the substance won’t change. The amount of heat energy required to change a unit of mass from a solid to a liquid without any change of temperature is the latent heat of fusion. If it’s necessary to increase the temperature of a melted substance, additional heat energy must be provided. The latent heat of vaporization is the amount of heat energy required to change a unit of mass of a liquid to a gas without a temperature change.
To condense a gas to a liquid, the gas must be cooled to the condensation point. After condensation, the liquid will have the same temperature as the gas; the temperature is still at the condensation point. To be cooled further, more heat energy should be released.
2. The liquid refrigerant in the indoor coils picks up heat from the indoor air and evaporates. In the gaseous state, it’s pumped to the outdoor coils, where it releases vaporization heat and condenses to the liquid state. The heat is transferred to the outdoor air, and the liquid refrigerant continues to circulate to the indoor coils to repeat the cooling cycle.
3.
Changing from a to a is called and happens at the _______ point.
solid liquid melting melting/fusion
liquid gas evaporation/boiling evaporation/boiling
gas liquid condensation condensation
liquid solid freezing freezing
