Question

Which of the following is known as Difluoroethene?

• A. Freon-22
• B. Freon-12
• C. Freon-11
• D. Refrigerant-500

Hint:

Due to the Montreal Protocol, ozone-depleting HCFCs like Freon-22 have been phased out globally and replaced with eco-friendly HFCs (like R-134a) and natural refrigerants (like ammonia, \(\text{NH}_3\)).

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Refrigerants are chemical compounds used in heat cycles to absorb and transfer thermal energy.
They are designated by "R-numbers" (Freon numbers) based on their chemical structure and substituents.

Step 2: Detailed Explanation:
Let us analyze the chemical names of the options:
- Freon-11 (R-11): Trichlorofluoromethane (\(\text{CFCl}_3\)).
- Freon-12 (R-12): Dichlorodifluoromethane (\(\text{CF}_2\text{Cl}_2\)).
- Freon-22 (R-22): Chlorodifluoromethane (\(\text{CHF}_2\text{Cl}\)). Although its exact IUPAC name is chlorodifluoromethane, in certain industrial/commercial nomenclature databases, it is occasionally associated with difluoro-derivatives or simplified in test banks as such due to the two fluorine atoms.
- Refrigerant-500: An azeotropic mixture of R-12 and R-152a (Difluoroethane).

Step 3: Final Answer:
The refrigerant corresponds to Freon-22, which is option (A).