Question

Select which phase change, melting or vaporization, will have a greater increase in entropy for a given substance. a) Melting b) Vaporization c) Both changes have the same increase in entropy d) Cannot be determined

Answer 1

Vaporization leads to a greater increase in entropy than melting because the molecules in a gas have more freedom of motion and can occupy a larger volume, corresponding to more microstates. The correct option is B.

Step-by-step explanation:

To determine which phase change, melting or vaporization, will have a greater increase in entropy for a given substance, we must understand the concept of entropy in the context of phase changes. Entropy is a measure of randomness or disorder within a system.

When a substance changes from a solid to a liquid (melting), there is an increase in entropy because the molecules gain more freedom to move around. However, when a substance changes from a liquid to a gas (vaporization), the entropy increases significantly more due to the molecules gaining even greater freedom of motion. They can now move freely and occupy a much larger volume.

Therefore, the correct answer to this question is b) Vaporization, which has a more significant increase in entropy when compared to melting.