Which of the following would best describe the third law of thermodynamics?

Which of the following would best describe the third law of thermodynamics?

• A. Entropy increases in all conditions
• B. Entropy remains constant at absolute zero
• C. Entropy approaches zero as temperature approaches absolute zero
• D. Entropy cannot be measured

Answer: (C)

The third law of thermodynamics states that as the temperature of a system approaches absolute zero, the entropy of a perfect crystal approaches zero. This means that at absolute zero (0 Kelvin), a perfectly ordered system would theoretically have no entropy because there would be no disorder in the arrangement of its particles. Therefore, choice C correctly captures this principle, indicating that the disordered nature of the system diminishes as the temperature nears absolute zero. The other options do not correctly reflect the concept. For instance, stating that entropy remains constant at absolute zero misconstrues the behavior of entropy under such conditions. Moreover, while it’s true that entropy can increase in many processes, this does not apply universally or define the third law specifically. The last option suggests that entropy cannot be measured, which overlooks the foundational concepts of thermodynamics and how entropy can indeed be quantified for systems.

The third law of thermodynamics states that as the temperature of a system approaches absolute zero, the entropy of a perfect crystal approaches zero. This means that at absolute zero (0 Kelvin), a perfectly ordered system would theoretically have no entropy because there would be no disorder in the arrangement of its particles. Therefore, choice C correctly captures this principle, indicating that the disordered nature of the system diminishes as the temperature nears absolute zero.

The other options do not correctly reflect the concept. For instance, stating that entropy remains constant at absolute zero misconstrues the behavior of entropy under such conditions. Moreover, while it’s true that entropy can increase in many processes, this does not apply universally or define the third law specifically. The last option suggests that entropy cannot be measured, which overlooks the foundational concepts of thermodynamics and how entropy can indeed be quantified for systems.