How does the latent heat of steam at elevated pressures compare to its value at standard atmospheric pressure__________________?
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Answer: A. less
Explanation
At elevated operating pressures, the latent heat of vaporization of steam is lower than its value at standard atmospheric pressure. As system pressure rises toward the critical point, the energy required to vaporize water decreases progressively. Higher saturation temperatures at elevated pressures reduce the energy gap between saturated liquid and saturated vapor states. Latent heat of vaporization represents the specific enthalpy difference between saturated vapor and saturated liquid at a given pressure. Steam table data confirms that enthalpy of vaporization drops steadily as operating pressures and temperatures increase. Thermodynamic phase change behavior dictates that boiling requires less thermal energy under high-pressure confinement.
The latent heat of steam is never greater at elevated pressures because thermal energy requirements drop as pressure increases. Stating that latent heat remains equal ignores standard thermodynamic steam table data across varying pressure ranges. The relationship between latent heat and elevated pressure is predictable and well-documented in thermodynamic engineering.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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