ESS11
Prof. Jin-Yi Yu
Man-Made Sources for CFCs
qThere are two kinds of CFCs: freon-11 (CCl3F) and freon-12 (CCl2F2).
q
qFreon-11 has been used:
q      (1) as a propellant in spray cans
q      (2) as a blowing agent for producing foams
q      (3)  to clean semiconductor chips.
q
qFreon-12 has been used as
q      (1) a refrigerant
q      (2) working fluid in most car air conditioners.
(from The Earth System)