The normal atmospheric boiling point temperature of ammonia is___________________?
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Answer: C. – 33.3°C
Explanation
The normal atmospheric boiling point of ammonia is approximately –33.3°C. At standard atmospheric pressure, liquid ammonia boils and absorbs latent heat at this specific sub-zero temperature. This thermal property makes ammonia an excellent refrigerant for medium and low-temperature industrial applications. Boiling point data at one atmosphere establish the baseline volatility of any chemical substance used in cooling. Anhydrous ammonia requires pressurized containment at room temperature to maintain its liquid state. Thermodynamic saturation tables list ammonia properties across a wide temperature and pressure spectrum.
Industrial ice plants and food freezing facilities utilize ammonia's low boiling point for efficient heat removal. Handling a fluid that boils well below room temperature requires robust pressure vessels and safety piping. Operators must wear appropriate personal protective equipment when servicing systems containing liquid ammonia. A boiling point of –100°C is far too low and applies to cryogenic gases like nitrogen rather than ammonia. A boiling point of –50°C underestimates the standard atmospheric saturation temperature of ammonia significantly. A boiling point of 0°C is the freezing point of water, which does not match ammonia thermodynamic data.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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