Which concept describes the tendency of a system to move toward disorder?

• A. Equilibrium
• B. Steady State
• C. Balance
• D. Entropy

Answer: (D)

The concept being tested is entropy, which is a measure of disorder or randomness in a system. In isolated systems, natural processes tend to move toward greater disorder because there are many more ways for energy and matter to be arranged in a disordered, higher-entropy state. This drive toward more probable configurations is the essence of the second law of thermodynamics, so entropy describes the tendency to become more disordered as processes unfold. Equilibrium is about a state where macroscopic properties stop changing, which is often the result of entropy reaching a maximum, but the defining idea in this question is the move toward disorder itself. A steady state involves ongoing processes with constant outputs and inputs, not a blanket move toward disorder. Balance is a general notion of stability, not the specific probabilistic push toward increased randomness.