Which is not a refrigerant ?

ANS:D - C₂H₄Cl₂

C2H4Cl2 (1,2-Dichloroethane) is not typically used as a refrigerant. So, the correct answer is: C2H4Cl2 C2H4Cl2, also known as 1,2-dichloroethane, is a chemical compound consisting of two carbon atoms, four hydrogen atoms, and two chlorine atoms. It is a colorless liquid with a chloroform-like odor. 1,2-Dichloroethane has various industrial applications, but it is not commonly used as a refrigerant. Instead, it has been historically used as a solvent for various organic materials, as a pesticide, and in the production of vinyl chloride, which is a precursor for polyvinyl chloride (PVC) plastics. Due to its toxicity and potential environmental and health hazards, the use of 1,2-dichloroethane has decreased over time, and it is now regulated or restricted in many countries. In refrigeration and air conditioning applications, safer and more environmentally friendly refrigerants like ammonia (NH3), sulfur dioxide (SO2), and chlorofluorocarbons (CFCs) or hydrochlorofluorocarbons (HCFCs) derivatives are typically used instead of 1,2-dichloroethane.