During the phase change in which heat is being added but the temperature remains constant, the heat energy is used to break the bonds in the molecules.
A phase change is the conversion of one state of matter to another. e.g. solid to liquid or liquid to gas.
Substances can exists in three states namely;
In a change of phase, heat energy is needed to break the existing bonds between the molecules of the initial state. For example, heat energy is needed to break the bonds of ice to form water.
However, during this phase change, the temperature remains constant.
Therefore, during the phase change in which heat is being added but the temperature remains constant, the heat energy is used to break the bonds in the molecules.
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