Critical temperature represents the thermal threshold above which _____________________?
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Answer: A. a gas will never liquefy
Explanation
Critical temperature is the threshold above which a gas cannot be liquefied regardless of how much pressure is applied. At temperatures exceeding this specific point, thermal kinetic energy overcomes intermolecular attractive forces entirely. No amount of mechanical compression can force a gas into a liquid state if its temperature is above critical. Every pure substance has a unique critical temperature and critical pressure defining its phase boundary limits. The vapor-liquid coexistence curve terminates precisely at the critical point on standard phase diagrams. Above the critical temperature, the fluid exists as a supercritical fluid exhibiting unique solvent properties.
A gas will never liquefy above its critical temperature, making immediate liquefaction impossible under those thermal conditions. Water evaporation occurs across a wide range of temperatures well below its high critical thermal threshold. Water definitely evaporates at ambient temperatures, disproving any notion that it remains permanently liquid.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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