The amount of energy transferred during the phase change is 2494 J.
we can use the following equation, in order to calculate the amount of energy transferred during the phase change. The heat of fusion is the change in its enthalpy resulting from providing energy, typically heat, to a specific quantity of the substance to change its state from a solid to a liquid, at constant pressure.
Energy = mass * latent heat of fusion
The latent heat of fusion is the amount of energy required to melt one gram of a substance. Ethanol, the latent heat of fusion is 249.4 J/g.
From the cooling curve, we can see that the mass of the ethanol sample is 10.0 g. Therefore, the amount of energy transferred during the phase change is:
Energy = 10.0 g * 249.4 J/g = 2494 J