Among the options below, which refrigerant possesses the lowest freezing point_______________?
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Answer: D. Freon-22
Explanation
Freon-22 possesses an extremely low freezing point suitable for very low-temperature refrigeration. Refrigerants must remain liquid well below operating temperatures to prevent system freezing. Low freezing points prevent blocked expansion valves in deep-freeze applications. Halocarbon refrigerants like Freon-22 offer favorable thermodynamic and physical properties. Freezing points mark the temperature where liquid refrigerants solidify into ice. Environmental regulations have phased out many chlorofluorocarbon refrigerants globally.
Industrial freezer plants and cascade systems require refrigerants with very low freezing points. Food freezing tunnels utilize low-temperature refrigerants to rapidly preserve perishable items. Selecting appropriate refrigerants prevents evaporator freeze-up failures in cold climates. Freon-12 has a higher freezing point and is used in medium-temperature refrigeration. Ammonia has excellent thermodynamic properties but higher freezing risks in certain setups. Carbon dioxide operates at very high pressures and has different freezing characteristics.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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