The correct IUPAC name of Freon 12 is

The correct answer is Option (2) → 1,1-Dichloro-1,1-difluoromethane

Freons are the chlorofluorocarbon compounds of methane and ethane. Freon 12 is \( \ce{CCl2F2} \): a single carbon atom carrying two chlorine and two fluorine atoms. In IUPAC names halogens are written as prefixes (chloro, fluoro) in alphabetical order, so chloro comes before fluoro:

    \( \displaystyle \ce{CCl2F2}:\ \text{dichlorodifluoromethane} \)

With only one carbon atom the locants are not needed, but written in full they are all 1, which gives the name in Option (2), 1,1-dichloro-1,1-difluoromethane.

NCERT (2026-27 edition):
Freons