What does ozone in the stratosphere above the earth consist of?
a. Molecules containing 2 oxygen atoms.
b. Molecules containing 3 oxygen atoms.
c. Molecules containing 4 oxygen atoms.
d. Molecules containing 5 oxygen atoms correct answers B
Which of the following refrigerants has the lowest global warming potential?
a. R-134a
b. R-407C
c. R-410A
d. R-600a correct answers D
Which of the following gases is used as the baseline measurement for global warming potential?
a. Ammonia
b. Carbon Dioxide
c. CFC-12
d. Propane correct answers B
Which type of refrigerant typically has the lowest global warming potential?
a. HCFCs
b. HFOs
c. HFCs
d. All are equal correct answers B
What is the state of refrigerant entering the compressor of a refrigeration system?
,a. Low pressure subcooled liquid
b. Low pressure superheated vapor
c. High pressure subcooled liquid
d. High pressure subcooled vapor correct answers B
How does the global warming potential of R-410A compare to that of carbon dioxide?
a. It is lower.
b. They are equal.
c. It is hundreds of times greater.
d. It is thousands of times greater. correct answers D
How do the global warming potentials of isobutane (R-600a), propane (R-290), and R-441A
compare to the GWPs of HFC-134a, R404A, and R-410A?
a. They are significantly higher.
b. They are significantly lower.
c. They are approximately equal
d. They are slightly higher. correct answers B
What are the characteristics of hydrofluoroolefins (HFOs)?
a. Non-ozone depleting and have high global warming potentials.
b. Non-ozone depleting and have low global warming potentials.
c. Ozone depleting and have high global warming potentials.
d. Ozone depleting and have low global warming potentials. correct answers B
Why are HFO refrigerants less flammable than hydrocarbon refrigerants?
a. They contain chlorine.
b. They contain bromine.
, c. They contain fluorine.
d. They contain carbon. correct answers C
Which of the following refrigerants is an HFO?
a. R-1234yf
b. R-123
c. R-134a
d. All three are HFOs correct answers A
What characteristics of HFC refrigerants make them damaging to the environment?
a. They are toxic to plants and animals at low doses.
b. They contain chlorine which damages the ozone layer.
c. They have high Ozone Depletion Potential (ODP)
d. They can have very high global warming potentials. correct answers D
Why are some of the hydrofluoroolefins classified as A2L?
a. They have toxicity characteristics.
b. They are less flammable than hydrocarbon refrigerants, but most are still mildly flammable.
c. They are prohibited for use in the U.S.
d. They have ozone depleting potentials and have low global warming potentials. correct answers
B
How many ozone molecules can each chlorine atom in the stratosphere destroy?
a. 1,000 molecules
b. 100,000 molecules
c. 100,000,000 molecules
d. None. Chlorine is not the element in refrigerant that harms ozone. correct answers B