Chapter 14.1, Problem 5RQ

Interpretation Introduction

Interpretation: The reason for change of state to be considered a physical change and not a chemical change needs to be explained.

Concept introduction: A physical change is the one that does not involve the transformation of the original material into a different material whereas a chemical change does. In a physical change the original, material remains the same. Only its form gets changed. In a physical change no chemical bond is broken or formed whereas it occurs in case of a chemical bond.

Answer to Problem 5RQ

Change of state neither involves the transformation of the original material into a different material nor involves breaking and forming of a chemical bond.

Explanation of Solution

Change of state here means changing the physical state of a substance. For example- from solid to liquid, liquid to gas etc. During change of state, only inter-molecular forces get altered without changing the composition of the material. Thus no new material is formed and no chemical bonds are formed or broken.

Conclusion

Change of state follows the criteria of being a physical change. Thus it is a physical change.