Question

Freon used as refrigerant is

• A. ${\mathrm{CF}}_2={\mathrm{CF}}_2$
• B. ${\mathrm{CH}}_2{\mathrm{F}}_2$
• C. ${\mathrm{CCl}}_2{\mathrm{F}}_2$
• D. ${\mathrm{CF}}_4$

Answer 1

The correct option is C

${\mathrm{CCl}}_2{\mathrm{F}}_2$

The explanation for the correct option:

Option C: ${\mathrm{CCl}}_2{\mathrm{F}}_2$

• Freons are the Chlorofluorocarbons$\left(\mathrm{CFC}\right)$ compounds of methane and ethane.
• Chlorofluorocarbons have many applications because of their low toxicity and non-flammability.
• These are usually produced for aerosol propellants, refrigeration, and air conditioning purposes.
• Dichlorodifluoromethane $\left({\mathrm{CCl}}_2{\mathrm{F}}_2\right)$ also known as Freon 12, is widely used as a refrigerant in refrigerators and air conditioners.

The explanation for incorrect options:

Option A: ${\mathrm{CF}}_2={\mathrm{CF}}_2$

• Polytetrafluoroethylene or Teflon is a synthetic polymer of tetrafluoroethylene (${\mathrm{CF}}_2={\mathrm{CF}}_2$).
• It is used in musical instruments, pharmaceuticals, kitchenware, lubricants, etc.
• Hence incorrect option.

Option B: ${\mathrm{CH}}_2{\mathrm{F}}_2$

• Difluoromethane $\left({\mathrm{CH}}_2{\mathrm{F}}_2\right)$ is a colourless and flammable gas that is used as a primary refrigerant.
• This is an important component of some refrigeration mixtures and also acts as a reactive ion etching gas in semiconductor material processing applications.
• Hence incorrect option.

Option D: ${\mathrm{CF}}_4$

• Carbon tetrafluoride or Tetrafluoromethane $\left({\mathrm{CF}}_4\right)$ is a colourless and odourless gas.
• It is a low-temperature refrigerant.
• It is also used in electronics microfabrication and neutron detectors.
• Hence incorrect option.

Hence, option (C) is the correct answer.