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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