Final answer:
b. (R-12), which is a chlorofluorocarbon (CFC), has the lowest solubility in refrigerant oils when compared to CO2, R-22, and NH3, due to its chemical properties and boiling point.
Step-by-step explanation:
The question asks which refrigerant oil has the lowest solubility in certain substances. To address this, we must understand solubility in the context of refrigerants.
Among the options given, R-12, or Freon-12, which is a chlorofluorocarbon (CFC), generally exhibits lower solubility in refrigerant oils compared to other refrigerants like CO2 (carbon dioxide), R-22 (hydrochlorofluorocarbon-22), and NH3 (Ammonia). The refrigerant oils are designed to be miscible with the refrigerant used in the system.
Freon-12 has a boiling point of -29.8 °C, which means at room temperature (-25°C), it exists as a gas and would not be as soluble in oil as the other options.
This is important for maintaining the performance of refrigeration systems, as oils with low solubility could lead to issues like oil logging in the system.
On the other hand, components like CO2, R-22, and NH3 have different chemical properties that result in better solubility in oils. For example, R-22 is a hydrochlorofluorocarbon, which is more miscible with refrigerant oils compared to CFCs like R-12. Therefore, for the queried refrigerants, Freon-12 (R-12) would have the lowest solubility in refrigerant oil.