Gases adhere most closely to the ideal equation of state, PV = nRT, under conditions of____________________?
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Answer: A. Low pressure & high temperature
Explanation
Low pressure reduces molecular crowding making intermolecular forces negligible in real gas systems. High temperature increases kinetic energy overcoming attractive forces between individual gas molecules. Under these extreme conditions real gases closely approximate ideal gas PV equals nRT behavior. Ideal gas law assumes zero molecular volume and zero intermolecular attractive forces between gas particles. Real gases deviate significantly from ideal behavior under high pressures and low temperatures. Compressibility factor approaches unity when gases are maintained at low pressure and high temperature.
Atmospheric pressure calculations often assume air behaves as an ideal gas with minimal error. Chemical engineers use ideal gas laws for preliminary reactor sizing under low pressure conditions. Thermodynamic calculations for high pressure synthesis require real gas equations instead of ideal laws. High pressure forces molecules close together causing significant intermolecular volume errors in calculations. Low temperature reduces molecular kinetic energy allowing attractive forces to dominate gas behavior. Stating none of these is incorrect because low pressure and high temperature correctly define ideal conditions.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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