The gas used in a refrigerator is - (1) cooled down on flowing (2) heated up on flowing (3) cooled down when compressed (4) cooled down when expanded

The gas used in a refrigerator is - (1) cooled down on flowing (2) heated up on flowing (3) cooled down when compressed (4) cooled down when expanded
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(4) cooled down when expanded Explanation: Common refrigerants used in various applications are ammonia, sulfur dioxide, and non-halogenated hydrocarbons such as propane. Compressing these gasses into liquids they are made to give up their heat.
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