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Absorption refrigeration: identify the refrigerant pairs For aqua–ammonia and lithium-bromide–water absorption refrigeration systems, identify the refrigerants respectively. Choose the correct pair in the stated order.

Difficulty: Easy

Water and water
Water and lithium bromide
Ammonia and lithium bromide
Ammonia and water

Correct Answer: Ammonia and water

Explanation:

Given systems

Aqua–ammonia (NH₃–H₂O)
Lithium bromide–water (LiBr–H₂O)

Concept/Approach
In aqua–ammonia systems, ammonia is the refrigerant and water is the absorbent. In LiBr–water systems, water is the refrigerant and lithium bromide is the absorbent.

Final Answer
Ammonia and water

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