Practice question · Select all that apply
Which statements help explain why cooling becomes progressively harder near absolute zero?
Hints
- Three are established results; one contradicts the third law.
- Unattainability is structural, not a limitation of equipment.
Show the answer
- A. Heat capacities must vanish as the temperature approaches zero
- B. Metals show a linear electronic and a cubic phonon contribution
- D. Some crystals retain residual entropy at low temperature
Why
Heat capacities must vanish for the entropy integral to converge, metals show , and imperfect crystals such as CO keep residual entropy. Unattainability is a consequence of the law itself, not of imperfect engineering.
Practise The Third Law and Low Temperatures
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