Textbook Question
(a) What is the difference between a state and a microstate of a system?
Ch.19 - Chemical Thermodynamics
Chapter 19, Problem 31
Would each of the following changes increase, decrease, or have no effect on the number of microstates available to a system: (a) increase in temperature, (b) change of state from liquid to gas?
Verified step by step guidance1
Understand the concept of microstates: In thermodynamics, a microstate refers to a specific configuration of the locations and energies of the particles in a system. The number of microstates is related to the entropy of the system, with more microstates corresponding to higher entropy.
Consider the effect of temperature on microstates: Increasing the temperature of a system generally increases the kinetic energy of its particles. This increase in energy allows particles to access more configurations, thereby increasing the number of microstates.
Analyze the change of state from liquid to gas: When a substance changes from a liquid to a gas, the particles move from being closely packed to being much more spread out. This transition allows for a greater number of possible arrangements and energy distributions, thus increasing the number of microstates.
Relate microstates to entropy: Since entropy is a measure of the number of microstates, any change that increases the number of microstates will also increase the entropy of the system.
Summarize the effects: (a) An increase in temperature increases the number of microstates. (b) A change of state from liquid to gas increases the number of microstates.
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Microstates
Microstates refer to the specific configurations or arrangements of particles in a system that correspond to a particular macroscopic state. The number of microstates is crucial in determining the entropy of a system, as higher entropy indicates a greater number of possible microstates. Understanding microstates helps in analyzing how changes in conditions, like temperature or phase, affect the system's disorder and energy distribution.
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01:23
The Boltzmann Equation
Temperature and Energy Distribution
Temperature is a measure of the average kinetic energy of particles in a system. An increase in temperature generally leads to greater energy distribution among particles, allowing them to occupy a wider range of microstates. This increased energy can enhance the system's ability to explore different configurations, thereby increasing the number of available microstates.
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Phase Changes
Phase changes, such as the transition from liquid to gas, significantly affect the number of microstates. In a gas, particles are more dispersed and have greater freedom of movement compared to a liquid, resulting in a much larger number of accessible microstates. This transition typically leads to an increase in entropy, reflecting the greater disorder and variety of arrangements in the gaseous state.
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Related Practice
Textbook Question
(b) As a system goes from state A to state B, its entropy decreases. What can you say about the number of microstates corresponding to each state?
Textbook Question
(c) In a particular spontaneous process, the number of microstates available to the system decreases. What can you conclude about the sign of ΔSsurr?
Textbook Question
Would each of the following changes increase, decrease, or have no effect on the number of microstates available to a system: (b) decrease in volume