Answer:
The temperature-time diagram is attached below
When ethanol is heating -120°C, its temperature rises till -114°C. Then the temperature remains constants at -114°C° till all of the ethanol is converted from Solid to Liquid. After that the temperature starts to rise again till 78°C. Then the temperature remains constants till all the liquid is converted into gas.
The slopes depends on rate of heating and specific heat capacity of ethanol.
The plateaus depend on rate of heating and latent heat of fusion and latent heat of vaporization.
