100% VERIFIED ANSWERS
1. As of what date did it become unlawful to knowingly release Class I
and Class II refrigerants into the atmosphere?
a. January 1, 1995
b. November 15, 1993
c. July 1, 1992
d. December 31, 1995
Correct Answer: c. July 1, 1992
Rationale: The Clean Air Act made it illegal to knowingly vent Class I
(CFCs) and Class II (HCFCs) refrigerants as of July 1, 1992. This date
applies specifically to the prohibition against knowingly releasing these
substances during maintenance, service, repair, or disposal of
appliances.
2. What is the ozone layer and why is it important to life on Earth?
a. A thin layer of CFCs and HCFCs in the troposphere that filters harmful
radiation
b. A protective shield in the stratosphere, extending approximately 6 to
30 miles above Earth, that filters the sun's harmful ultraviolet (UV) rays
c. A layer of R-22 refrigerant in the atmosphere that absorbs heat
d. A layer of oxygen molecules in the mesosphere that reflects sunlight
,Correct Answer: b. A protective shield in the stratosphere, extending
approximately 6 to 30 miles above Earth, that filters the sun's harmful
ultraviolet (UV) rays
Rationale: The ozone layer is found in the stratosphere and serves as
Earth's natural protection against harmful UV radiation. It is not
composed of refrigerants and is located approximately 6 to 30 miles
above the Earth's surface.
3. The atom found in CFC and HCFC refrigerants that destroys ozone in
the stratosphere is which of the following?
a. Fluorine
b. Carbon
c. Hydrogen
d. Chlorine
Correct Answer: d. Chlorine
Rationale: Chlorine atoms are released when CFC and HCFC refrigerants
are exposed to UV radiation in the stratosphere. These chlorine atoms
act as catalysts that destroy ozone molecules, while fluorine and
hydrogen do not participate in ozone destruction.
4. What is an ozone molecule made of?
a. Refrigerant compounds
b. Ammonia and oxygen
c. Three oxygen atoms (O3)
d. Oxygen and chlorine
,Correct Answer: c. Three oxygen atoms (O3)
Rationale: Ozone is a molecule composed of three oxygen atoms (O3).
It is formed in the stratosphere when UV radiation splits O2 molecules
and the free oxygen atoms combine with other O2 molecules to form
O3.
5. Which refrigerant is classified as a CFC?
a. R-134A
b. R-123
c. R-22
d. R-12
Correct Answer: d. R-12
Rationale: R-12 (dichlorodifluoromethane) is a chlorofluorocarbon
(CFC) that contains chlorine, fluorine, and carbon. R-134A is an HFC, R-
123 is an HCFC, and R-22 is an HCFC.
6. What is the name of the atom that attacks and destroys ozone
molecules?
a. CFC atoms
b. HCFC atoms
c. Chlorine and bromine atoms emitted into the atmosphere
d. Fluorine and carbon atoms
Correct Answer: c. Chlorine and bromine atoms emitted into the
atmosphere
Rationale: Both chlorine and bromine atoms are ozone-depleting
, substances. When released into the stratosphere, these atoms catalyze
the destruction of ozone molecules through a chain reaction process.
7. Which refrigerant is classified as an HFC?
a. R-134A
b. R-123
c. R-22
d. R-12
Correct Answer: a. R-134A
Rationale: R-134A (tetrafluoroethane) is a hydrofluorocarbon (HFC) that
contains no chlorine. HFCs have zero ozone depletion potential (ODP)
but are greenhouse gases with high global warming potential (GWP).
8. Describe how one chlorine atom can destroy up to 100,000 ozone
molecules.
a. Chlorine releases one oxygen atom and forms two O2 molecules,
leaving the chlorine free to attack another ozone molecule and repeat
the process
b. Chlorine locks up the ozone molecule and then goes after another
c. Chlorine converts ozone to bromine and then attacks more ozone
molecules
d. Chlorine can destroy 100,000 ozone molecules before it weakens
Correct Answer: a. Chlorine releases one oxygen atom and forms two
O2 molecules, leaving the chlorine free to attack another ozone
molecule and repeat the process
Rationale: The chlorine atom acts as a catalyst in a chain reaction. It