Question

in the metering device of an air - cooled air conditioner
the warm gas changes to a cool gas
the warm liquid changes to a cool liquid
the pressure on the gas is increased
the pressure on the liquid is increased
the gas condenses to a liquid

Explanation:

Step1: Understand metering device role

In an air - cooled air conditioner, the metering device throttles the high - pressure, warm liquid refrigerant coming from the condenser.

Step2: Analyze refrigerant state change

As it passes through the metering device, the pressure drops, and the warm liquid refrigerant changes to a cool liquid (with some flash - gas formation in some cases). This is because of the pressure drop across the metering device which causes a reduction in the refrigerant's temperature. The other options are incorrect: the warm gas changing to a cool gas is not the main function of the metering device; the pressure on the gas is not increased in the metering device; the pressure on the liquid is decreased; and gas condensing to a liquid occurs in the condenser, not the metering device.

Answer:

the warm liquid changes to a cool liquid