Chapter U3, Problem 13STP

Interpretation Introduction

Interpretation:

The best hypothesis for the particle view of solid carbon dioxide when it sublimes needs to be determined.

Concept introduction:

During sublimation, a solid converts directly into gas without converting into liquid state and vice versa.

Answer to Problem 13STP

(D) Hypothesis D. The gas molecules move relatively far apart from one another when carbon dioxide sublimes.

Explanation of Solution

Reason for correct option:

In the solid state, the molecules of carbon dioxide are in compact form. They do not have space between them. During sublimation, solid carbon dioxide converts directly into gas. In gas phase, molecules are relatively far from each other. There is no such pattern followed by the gas molecules thus, hypothesis D is correct.

Conclusion

Reasons for incorrect options:

The gas molecules do not expand individually because in solid state the molecules are in compact form or there is no space between them. All the solid molecules together convert into gas molecules. The gaseous molecules have no space between them thus, they are not close to each other in the container. The gas molecules spread all over the container when carbon dioxide sublimes.The gas molecules collide on the surface of the container when carbon dioxide sublimes.

Thus, options A, B and C are incorrect.