Entropy
Definition
Entropy refers to the measure of disorder or randomness in a system. In chemistry, higher entropy means higher disorder and less predictability.
Analogy
Think of entropy like your bedroom. When it's clean, everything is in order and easy to find - low entropy. But as you use things and don't put them back, the room becomes more disordered - high entropy!
Related terms
Second Law of Thermodynamics: This law states that the total entropy of an isolated system can never decrease over time, meaning systems naturally progress towards a state of maximum entropy.
Gibbs Free Energy: A thermodynamic potential that measures the "usefulness" or process-initiating work obtainable from a system at constant temperature and pressure. It combines enthalpy and entropy into one value.
Microstates: In statistical mechanics, microstates refer to specific detailed configurations of a macroscopic system that may occur with a certain probability when defined by macroscopic variables such as energy, volume, or number of particles. The concept is closely linked to understanding entropy.
"Entropy" appears in:
Study guides (4)
Practice Questions (20+)
- Consider a reaction X + Y ⇌ XY. How can the entropy change from the particles be described?
- Consider a reaction XYZ ⇌ X + Y + Z. How can the entropy change from the particles be described?
- What happens to entropy as the temperature of a reaction increases?
- What is the entropy difference between 1 mol of hydrogen gas (H₂) and 1 mol of oxygen (O₂) at the same conditions?
- What changes would NOT increase entropy in a system?
- In which of the following reactions is entropy increasing?
- What tenet of the kinetic molecular theory (KMT) supports the positive correlation between entropy and temperature in ideal gases?
- What law states that the entropy of the universe increases in a spontaneous reaction?
- Which of the following would decrease the entropy of a system?
- Which gaseous molecules would have the largest entropy at 25°C and 1 atm?
- What temperature can zero entropy be achieved?
- Which reaction has the most positive entropy change under standard conditions?
- At a constant temperature, which of the following would increase entropy?
- Which of the following describes the relationship between volume and entropy?
- What is the general relationship between temperature and entropy for diatomic gases?
- In which of the following reactions is entropy increasing?
- True or false! Entropy can be measured BOTH absolutely and as a change.
- Which of the following statements is true about the entropy change of a system that absorbs heat from its surroundings?
- Which of the following statements is true about the relationship between entropy and kinetic control in a reaction?
- Which of the following statements is true about the relationship between entropy and enthalpy in a reaction?
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