A heating curve gives us information on how much energy is required to change the state of matter of a substance and at what temperature this change occurs.
The x-axis represents the heat to be added and the y-axis the temperature. On the graph, when a phase change occurs, the temperature will remain constant, obtaining a straight line.
The melting point is the temperature at which a substance changes from a solid to a liquid state. The melting point will be linked to the molar heat of fusion.
The boiling point is the temperature at which there is a change of state from liquid to gas, the boiling point is linked to the molar heat of vaporization.
The heat curve for this case will be:
