Which of the following refrigerants is categorized as CFC type?

The refrigerant R-11 is categorized as a chlorofluorocarbon (CFC). CFCs are a class of compounds that contain chlorine, fluorine, and carbon. They were widely used in refrigeration and air conditioning systems due to their efficient thermodynamic properties and stability. However, their use has been heavily regulated and phased out due to their contribution to ozone layer depletion.

R-11, in particular, was commonly used in large commercial and industrial refrigeration systems, as well as in chillers. Its significant impact on the ozone layer has led to the implementation of international agreements such as the Montreal Protocol, which aimed to reduce and eventually eliminate the use of ozone-depleting substances.

In contrast, R-22 is classified as a hydrochlorofluorocarbon (HCFC), which is less harmful to the ozone layer than CFCs but still poses some environmental risks. R-134a is a hydrofluorocarbon (HFC) and does not contain chlorine, making it ozone-friendly, while R-123 is an HFC that was developed to replace R-11 but with a lower ozone depletion potential than CFCs. Thus, R-11 stands out as the CFC in this context.