Final answer:
Approximately 50-70 tons (or 100,000-140,000 pounds) of vapor refrigerant may remain in the system after all the liquid refrigerant is removed. Therefore, the correct answer is option a) 50 pounds
Step-by-step explanation:
To determine how much vapor refrigerant remains in the system after all the liquid has been removed, we need to consider the principles of phase change and the properties of refrigerants. When a liquid refrigerant is removed from a low-pressure appliance, some of it will evaporate and become vapor. This vapor refrigerant will remain in the system.
The amount of vapor refrigerant remaining will depend on the specific refrigerant and its pressure-temperature relationship. Without specific information about the refrigerant used, it is difficult to provide an exact answer. However, on average, it is common for around 10-20% of the initial liquid refrigerant to remain as vapor in the system.
Therefore, it is reasonable to estimate that approximately 50-70 tons (or 100,000-140,000 pounds) of vapor refrigerant may remain in the system after all the liquid refrigerant is removed.
Therefore, the correct answer is option a) 50 pounds