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Material selection: condenser tubes for ammonia refrigeration For ammonia (NH3) refrigerating systems using shell-and-tube condensers, which tube material is appropriate considering compatibility and corrosion? Choose the correct material.

Difficulty: Easy

Copper
Aluminium
Steel
Brass

Correct Answer: Steel

Explanation:

Concept/ApproachAnhydrous ammonia is incompatible with copper and copper alloys (e.g., brass), which can suffer corrosion/stress corrosion cracking in ammonia service.

ThereforeSteel tubes are used for condensers/evaporators in ammonia systems.

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