Chapter 14.1, Problem 4RQ

Interpretation Introduction

Interpretation: Cooling curve for a sample of steam at ${120}^{\circ }C$ that condenses to liquid water and cools eventually to form ice at $0^{\circ }C$ is to be drawn.

Concept introduction: A cooling curve shows the changes in the physical state of a substance from gas to liquid or gas to solid with time in the form a graph where temperature is taken as the y-axis and time is taken as the x-axis.

Answer to Problem 4RQ

Here is the cooling curve.

  

Explanation of Solution

The graph above is the cooling curve. Point A represents steam at ${120}^{\circ }C$ . On cooling, steam condenses to form liquid water shown by point B. On further cooling, liquid water changes to form ice at $0^{\circ }C$ . The straight line between A and B shows transition of steam to liquid water and the straight line C shows transition of liquid water to ice. Here ice is at $0^{\circ }C$ .

Conclusion

Thus the above graph is a cooling curve for water for the given conditions of temperature and physical states.