Specific latent heat of fusion

The heat energy that is required for a material to undergo a change of phase (J). Specific latent heat of fusion... 

The curve crosses the y axis at a negative value of your choosing. Between the plateaus, the slope is approximately linear. The plateaus are crucial as they are the visual representation of the definition of latent heat. The first plateau is at 0°C and is short in duration as only 334kJ.kg 1 is absorbed in this time (specific latent heat of fusion). The next plateau is at 100 °C and is longer in duration as 2260kJ.kg-1 is absorbed (specific latent heat of vaporization). 

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