Chapter 14.1, Problem 6R

To determine

The description of the energy changes of the water from $-15°\text{C}$ to $120°\text{C}$ .

Explanation of Solution

Introduction:

The water undergoes either phase change or a rise in temperature due to heating. The latent heat causes the phase change and specific heat causes the rise in temperature.

The water at the temperature $-15°\text{C}$ remains as ice. When the ice of $-15°\text{C}$ heats up the temperature of the ice rises from $-15°\text{C}$ to $0°\text{C}$ . This part in the figure is shown by the curve a. Further, heating changes the ice of $0°\text{C}$ to water of $0°\text{C}$ . This part is shown by curve b in the figure. The temperature for part b remains the same and phase change takes place from ice to water.

The heating of the $0°\text{C}$ water causes a rise in the temperature of the water. The temperature of water rises up to $100°\text{C}$ and it is shown by curve c in the figure.

At the temperature, $100°\text{C}$ water starts boiling and further heating of boiling water causes the phase change of boiling water into steam. This part is shown by the curve d in the figure.The part e in the figure shows the rise in the temperature of the steam.

Conclusion:

Thus, the curve b, curve d shows the phase change and curve a, curve c, curve e shows the rise in temperature of water due to heating.