The critical pressure where the latent heat of vaporization for steam drops to zero is _____________ Kg/cm2 ?
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Answer: B. 225.65
Explanation
At the critical pressure point, the physical properties of liquid and vapor phases become identical. The latent heat of vaporization drops completely to zero when water reaches its critical pressure. Water's critical pressure is approximately two hundred twenty-one megapascals or two hundred twenty-five point six kilograms per square centimeter. Critical point represents the termination boundary of liquid and vapor phase equilibrium curves. Supercritical water exhibits unique solvent and transport properties used in advanced power cycles. Latent heat decreases steadily as operating pressure approaches the thermodynamic critical point.
Supercritical fossil fuel power plants operate above critical pressure to maximize cycle efficiency. Modern thermal power stations avoid boiling transition losses by operating in supercritical regimes. Chemical waste destruction uses supercritical water oxidation due to its exceptional solvent capability. Option A confuses critical pressure with standard temperature conversion values for freezing points. Option C represents standard atmospheric boiling points rather than critical pressure thresholds. Option D incorrectly associates absolute temperature values with the critical pressure metric.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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