Determine the sign of ΔS_sys for each process. b. water freezing

Verified step by step guidance

1. Identify the process: Water freezing is a phase change from liquid to solid.
2. Recall that entropy (ΔS) is a measure of disorder or randomness in a system.
3. Understand that in the liquid state, water molecules have more freedom of movement compared to the solid state.
4. Recognize that when water freezes, the molecules become more ordered as they form a crystalline structure.
5. Conclude that the entropy of the system decreases, so the sign of ΔS_sys is negative.

Key Concepts

Entropy (ΔS)

Entropy, denoted as ΔS, is a measure of the disorder or randomness in a system. In thermodynamics, a positive ΔS indicates an increase in disorder, while a negative ΔS signifies a decrease in disorder. Understanding how entropy changes during a process is crucial for predicting the spontaneity and feasibility of that process.

Phase Changes

Phase changes, such as freezing, involve transitions between solid, liquid, and gas states. During freezing, water transitions from a liquid to a solid state, which typically results in a decrease in entropy because the molecules become more ordered in the solid phase. Recognizing how phase changes affect entropy is essential for analyzing thermodynamic processes.

Second Law of Thermodynamics

The Second Law of Thermodynamics states that the total entropy of an isolated system can never decrease over time. This principle implies that spontaneous processes tend to increase the overall entropy of the universe. When considering processes like water freezing, it is important to evaluate how the entropy of the system and surroundings changes to determine the sign of ΔS.