1.
__ is a blend of two or more components whose equilibrium vapor phase and liquid phase compositions are the same at a given pressure.
Correct Answer
A. Azeotrope
Explanation
An azeotrope is a blend of two or more components whose equilibrium vapor phase and liquid phase compositions are the same at a given pressure. This means that the mixture behaves as if it were a single component, making it difficult to separate the components by fractional distillation.
2.
__ is a halogenated hydrocarbon containing one or more of the three halogens: fluorine, chlorine, and bromine.
Correct Answer
D. Halocarbon
Explanation
A halocarbon is a halogenated hydrocarbon that contains one or more of the three halogens: fluorine, chlorine, and bromine. This means that the compound has been chemically modified to include one or more of these halogens in its structure. Halocarbons have various applications, including as refrigerants, solvents, and propellants. They are also used in the production of plastics, pharmaceuticals, and agricultural chemicals.
3.
Chlorofluorocarbons (CFCs) consist of ___, ___, and __ .
Correct Answer
A. Chlorine, fluorine, carbon
Explanation
Chlorofluorocarbons (CFCs) are composed of chlorine, fluorine, and carbon. These compounds were commonly used in refrigerants, aerosol propellants, and foam-blowing agents. However, they have been found to be harmful to the ozone layer in the Earth's atmosphere. The chlorine atoms in CFCs are responsible for depleting the ozone layer by reacting with ozone molecules, breaking them apart. This reaction releases chlorine oxide, which can then catalytically destroy thousands of ozone molecules. The fluorine and carbon atoms in CFCs contribute to the stability and chemical properties of these compounds.
4.
CFCs are chemically very stable because they contain no __ .
Correct Answer
A. Hydrogen
Explanation
CFCs are chemically very stable because they contain no hydrogen. Hydrogen atoms are highly reactive and can participate in chemical reactions, leading to the breakdown of molecules. Since CFCs do not have any hydrogen atoms, they are less likely to undergo chemical reactions and remain stable in the environment.
5.
CFCs are damaging to the __ ozone layer.
Correct Answer
B. StratospHeric
Explanation
CFCs, or chlorofluorocarbons, are known to be harmful to the ozone layer. The ozone layer is located in the stratosphere, which is the second layer of the Earth's atmosphere. Therefore, the correct answer is "stratospheric."
6.
Of the three common types of refrigerants __ has the highest high ozone-depletion potential (ODP).
Correct Answer
A. CFCs
Explanation
CFCs, or chlorofluorocarbons, have the highest ozone-depletion potential (ODP) among the three common types of refrigerants. This means that CFCs have the greatest ability to deplete the ozone layer when released into the atmosphere.
7.
_ test methods are assumed by the EPA as the most effective methods for locating the general area of small leaks.
Correct Answer
A. Electronic and Ultrasonic
Explanation
Electronic and ultrasonic test methods are assumed by the EPA as the most effective methods for locating the general area of small leaks. These methods use specialized equipment to detect and measure the sound or electronic signals produced by the leak. By analyzing these signals, the general area of the leak can be identified. Other methods such as using a halide torch or soap bubble may not be as effective in locating small leaks. Therefore, the correct answer is electronic and ultrasonic.
8.
After evacuation of a system, if the pressure rises ABOVE ambient pressure, then ____.
Correct Answer
A. Trapped refrigerant is probably boiling-off .
Explanation
If the pressure rises above ambient pressure after evacuation of a system, it suggests that the trapped refrigerant is likely boiling off. This could be due to an increase in temperature or a decrease in pressure within the system, causing the refrigerant to change from a liquid to a gas state. This indicates that there may be a problem with the system, such as a leak or a malfunctioning component.
9.
In cases where the refrigerant cannot be reclaimed due to contamination with other refrigerants, the refrigerant __ .
Correct Answer
B. Must be destroyed by incineration at a approved facility
10.
The system vacuum gauge should be connected __ .
Correct Answer
B. As close as possible to the system being evacuated
Explanation
The system vacuum gauge should be connected as close as possible to the system being evacuated in order to accurately measure the level of vacuum in the system. Placing the gauge close to the system ensures that it is measuring the actual vacuum level at the location where it is most important. This allows for more precise monitoring and control of the vacuum process. Connecting the gauge close to the system being evacuated also helps to minimize any potential inaccuracies or errors that may occur due to distance or other factors.
11.
Manufacture of CFCs will be banned after December 31, __ .
Correct Answer
B. 1995
Explanation
The manufacture of CFCs, or chlorofluorocarbons, was banned after December 31, 1995. This ban was implemented due to the harmful effects of CFCs on the ozone layer. CFCs were commonly used in aerosol propellants, refrigerants, and foam-blowing agents. The ban aimed to protect the ozone layer and reduce the depletion of ozone in the Earth's atmosphere.
12.
A second category of refrigerants currently available is the hydrochlorofluorocarbons (HCFCs). Although they contain chlorine, which is damaging to the ozone layer, they also contain_________, which makes them chemically less stable once they enter the atmosphere.
Correct Answer
A. Hydrogen
Explanation
HCFCs contain hydrogen, which makes them chemically less stable once they enter the atmosphere.
13.
Under EPA's regulations, reclaimed refrigerant must meet __ standards for purity before it can be resold. .
Correct Answer
A. ARI-700
Explanation
Under EPA's regulations, reclaimed refrigerant must meet ARI-700 standards for purity before it can be resold. ARI-700 is a standard set by the Air-Conditioning, Heating, and Refrigeration Institute (ARI) that specifies the purity requirements for reclaimed refrigerant. This standard ensures that the reclaimed refrigerant is free from contaminants and meets the necessary quality standards for safe and efficient use. The other options, ARI-740, SAE 1792, and EPA 1992, are not mentioned in the context of the question and do not pertain to the purity standards for reclaimed refrigerant.
14.
__ recovery devices are so named because they depend on components of the system; that is, they capture refrigerant with the assistance of components in the air conditioning or refrigeration equipment they are emptying.
Correct Answer
A. System-dependent
Explanation
Recovery devices are named "system-dependent" because they rely on the components of the air conditioning or refrigeration system to capture refrigerant. This means that the devices use the existing components of the system to assist in the recovery process, rather than being self-contained or independent from the system.
15.
All devices used for refrigerant recovery must meet __ standards.
Correct Answer
A. EPA
Explanation
All devices used for refrigerant recovery must meet EPA standards. The EPA (Environmental Protection Agency) sets regulations and standards for the safe handling and disposal of refrigerants, including the recovery of refrigerants from appliances and equipment. These standards ensure that the recovery process is done in an environmentally responsible manner, preventing the release of harmful substances into the atmosphere. Meeting EPA standards is important for maintaining the integrity of the environment and protecting human health.
16.
List one HCFC:
Correct Answer
C. R22
Explanation
R22 is a hydrochlorofluorocarbon (HCFC) that was commonly used as a refrigerant in air conditioning and refrigeration systems. It has properties that make it suitable for cooling applications, such as low boiling point and high heat capacity. However, due to its ozone depletion potential, R22 is being phased out and replaced with more environmentally friendly alternatives.
17.
Refrigerants which contain no chlorine at all are called __
Correct Answer
C. HFCs
Explanation
Refrigerants that contain no chlorine at all are called HFCs.
18.
CHF2CF3 refrigerant is a __ .
Correct Answer
A. HFC
Explanation
CHF2CF3 refrigerant is classified as an HFC (hydrofluorocarbon). HFCs are a type of synthetic refrigerant that does not contain chlorine and is considered to have a lower impact on the ozone layer compared to other types of refrigerants. HFCs are commonly used in various cooling and refrigeration systems.
19.
Ozone in the stratosphere consists of' molecules containing __ oxygen atom(s).
Correct Answer
C. 3
Explanation
Ozone in the stratosphere consists of molecules containing three oxygen atoms.
20.
__ in refrigerants causes ozone destruction.
Correct Answer
A. Chlorine
Explanation
Chlorine in refrigerants causes ozone destruction. Chlorine reacts with ozone molecules in the stratosphere, breaking them apart and depleting the ozone layer. This reaction is known as ozone depletion. Fluorine, on the other hand, does not cause ozone destruction. Therefore, the correct answer is chlorine.
21.
CFCs are able to reach the stratosphere because __ .
Correct Answer
A. They are chemically very stable
Explanation
CFCs are able to reach the stratosphere because they are chemically very stable. This means that they do not easily break down or react with other substances in the lower atmosphere. As a result, they can be transported upward into the stratosphere where they can cause damage to the ozone layer.
22.
The lower case letter following the refrigerant number, as in 134a for example, is the:
Correct Answer
C. Form of the isomer
Explanation
The lower case letter following the refrigerant number indicates the form of the isomer. In the example given, "134a", the "a" represents a specific isomer of the refrigerant. Isomers are molecules that have the same chemical formula but different structural arrangements. Therefore, the letter following the refrigerant number helps to identify the specific isomer being referred to.
23.
________ refrigerants are toxic.
Correct Answer
B. Group 2
Explanation
Refrigerants in Group 2 are toxic.
24.
__ refrigerants are nonflammable mixtures of group 1 and 3 refrigerants, which are nonflammable as formulated but whose composition can become flammable due to fractionation under some leakage situations.
Correct Answer
D. Group 4
Explanation
Refrigerants in Group 4 are nonflammable mixtures of group 1 and 3 refrigerants. These mixtures are initially nonflammable when formulated, but they can become flammable if there is fractionation under certain leakage situations. This means that the composition of the refrigerant can change, leading to the potential for flammability.
25.
__ refrigerants are flammable but not toxic.
Correct Answer
C. Group 3
Explanation
Refrigerants in Group 3 are flammable but not toxic. This means that while they can potentially catch fire, they do not pose a risk of causing harm through toxicity. It is important to handle and store these refrigerants with caution to prevent any accidents or fires.
26.
__ refrigerants do not show flame propagation.
Correct Answer
A. Group 1
Explanation
Refrigerants in Group 1 do not show flame propagation.
27.
R-134a tanks are __________.
Correct Answer
A. Light blue
28.
Disposable cylinders are manufactured to specifications established by the_.
Correct Answer
B. DOT
Explanation
Disposable cylinders are manufactured to specifications established by the DOT, which stands for the Department of Transportation. The DOT sets standards and regulations for the safe transportation of hazardous materials, including cylinders that contain gases or liquids. These specifications ensure that the cylinders are designed and manufactured to meet certain safety requirements, such as pressure ratings, valve specifications, and material composition. Compliance with DOT regulations is necessary to ensure the safe handling, storage, and transportation of these cylinders.
29.
Every refrigerant cylinder is equipped with a device that will automatically vent pressure from the cylinder before it reaches the rupture point. What is this devise called?
Correct Answer
A. Safety (pressure) relief valve
Explanation
The device that automatically vents pressure from a refrigerant cylinder before it reaches the rupture point is called a safety (pressure) relief valve. This valve is designed to release excess pressure in order to prevent the cylinder from exploding or causing any damage. It is an important safety feature in refrigerant cylinders to ensure the safe handling and storage of the refrigerant.
30.
Refillable cylinders are regulated in their design, fabrication and testing by the _________ for use in the transportation of refrigerants-
Correct Answer
B. DOT
Explanation
Refillable cylinders used for transporting refrigerants are regulated in their design, fabrication, and testing by the DOT (Department of Transportation). The DOT sets standards and regulations to ensure the safety and integrity of these cylinders during transportation. They establish guidelines for the construction, materials, pressure ratings, and testing procedures to ensure that the cylinders can safely contain and transport refrigerants without any risk of leakage or failure.
31.
Capturing and ultimately eliminating the use of chlorofluorocarbons is being done in the United States to stop damage to the __ ozone layer.
Correct Answer
A. StratospHeric
Explanation
The correct answer is "Stratospheric." The question is asking about the reason for capturing and eliminating the use of chlorofluorocarbons in the United States. The purpose is to prevent damage to the ozone layer, specifically the stratospheric ozone layer. Chlorofluorocarbons are known to deplete the ozone layer, particularly in the stratosphere, which is why efforts are being made to stop their use.
32.
State and local governments may establish laws that contain __ regulations than Clean Air Act/EPA regulations.
Correct Answer
A. Stricter
Explanation
State and local governments have the authority to create laws that are more stringent or stricter than the regulations set by the Clean Air Act and the Environmental Protection Agency (EPA). This means that these governments can impose additional requirements or limitations on air quality standards and emissions control measures, going beyond the minimum standards set by the federal government. Therefore, the correct answer is "stricter".
33.
The Clean Air Act __ .
Correct Answer
D. All the above
Explanation
The Clean Air Act encompasses all of the mentioned actions. It calls for the phase-out of CFC/HCFC production, prohibits CFC/HCFC venting as of July 1, 1992, and requires the EPA to set standards for equipment and technicians.
34.
Before you dispose of any appliance containing refrigerant, you must recover the refrigerant.
Correct Answer
D. All three
Explanation
All three options, CFC, HFC, and HCFC, require the recovery of refrigerant before disposing of any appliance containing them. This means that regardless of the type of refrigerant used in the appliance, it is necessary to recover the refrigerant before disposal to prevent its release into the environment and potential harm to the ozone layer.
35.
CFCs can no longer be manufactured or imported into the United States after _____
Correct Answer
D. December 31, 1995
Explanation
CFCs, or chlorofluorocarbons, are harmful to the ozone layer and contribute to ozone depletion. In order to protect the ozone layer, the United States implemented regulations to phase out the production and importation of CFCs. The correct answer, December 31, 1995, indicates the date when CFCs could no longer be manufactured or imported into the United States.
36.
Recovery cylinders are painted __ in the shoulder area and twelve inches down the side.
Correct Answer
C. Yellow
Explanation
Recovery cylinders are painted yellow in the shoulder area and twelve inches down the side.
37.
Refrigerant cylinders must bere-tested at ______ intervals.
Correct Answer
A. Five-year
Explanation
Refrigerant cylinders must be re-tested at five-year intervals. This means that every five years, the cylinders need to undergo a testing process to ensure their safety and effectiveness. This is important because refrigerant cylinders contain potentially hazardous substances, and regular testing helps to prevent any leaks or malfunctions that could lead to accidents or damage. By re-testing every five years, the cylinders can be properly maintained and any potential issues can be identified and addressed in a timely manner.
38.
Chemically, oxygen is 02, and ozone is _____.
Correct Answer
C. O3
Explanation
Ozone is chemically represented as O3. This is because ozone is composed of three oxygen atoms bonded together. In contrast, oxygen is represented as O2, as it consists of two oxygen atoms bonded together.
39.
After __ individuals servicing and disposing of air conditioning and refrigeration equipment are prohibited from knowingly venting refrigerant into the atmosphere.
Correct Answer
B. July 1, 1992
Explanation
On July 1, 1992, individuals servicing and disposing of air conditioning and refrigeration equipment were prohibited from knowingly venting refrigerant into the atmosphere.
40.
Under the EPA equipment certification requirement, mandatory equipment certification would go into effect on __ .
Correct Answer
A. November 15, 1993
41.
Under the EPA Final Rule, technician certification requirements would go into effect on
Correct Answer
C. November 14, 1994
Explanation
The EPA Final Rule implemented technician certification requirements, which means that technicians working in certain industries would be required to obtain certification. This rule went into effect on November 14, 1994.
42.
______ means to clean refrigerant for reuse by oil separation and single or multiple passes through devices, such as replaceable core filter-driers, which reduce moisture, acidity and particulate matter.
Correct Answer
B. Recycling
Explanation
Recycling refers to the process of cleaning refrigerant for reuse by removing impurities such as moisture, acidity, and particulate matter. This is achieved through oil separation and multiple passes through devices like replaceable core filter-driers.
43.
__ requires chemical analysis of the refrigerant to verify that the ARI 700 Purity Specifications are met.
Correct Answer
C. Reclamation
Explanation
Reclamation is the process of restoring or recovering a substance to its original or usable state. In the context of refrigerants, reclamation refers to the process of purifying and treating used refrigerants to remove impurities and contaminants. This ensures that the refrigerant meets the purity specifications set by ARI 700. Therefore, reclamation requires chemical analysis of the refrigerant to verify its compliance with these specifications.
44.
__ means, to remove refrigerant in any condition from a system and store it in an external container without necessarily testing or processing it in any way.
Correct Answer
A. Recovery
Explanation
Recovery means to remove refrigerant in any condition from a system and store it in an external container without necessarily testing or processing it in any way. This process is focused on collecting the refrigerant for later use or disposal, without any additional steps such as cleaning or filtering. It is simply the act of extracting the refrigerant from the system and storing it elsewhere.
45.
Used disposable refrigerant cylinders can be _____. '
Correct Answer
A. Recycled with other scrap metal after they are emptied and rendered useless
Explanation
Used disposable refrigerant cylinders can be recycled with other scrap metal after they are emptied and rendered useless because they are no longer suitable for their intended purpose. Once the cylinders are emptied and no longer contain any refrigerant, they can be treated as scrap metal and recycled along with other metal materials. This helps to reduce waste and promote environmental sustainability.
46.
The internal pressure of a cylinder with one pound of liquid refrigerant is __ the internal pressure of a full 50-pound cylinder.
Correct Answer
D. The same as
Explanation
The internal pressure of a cylinder with one pound of liquid refrigerant is the same as the internal pressure of a full 50-pound cylinder. This means that the amount of refrigerant in the cylinder does not affect the internal pressure.
47.
Refillable containers must meet __ requirements.
Correct Answer
A. DOT
Explanation
Refillable containers must meet DOT requirements. DOT stands for the Department of Transportation, which sets regulations and standards for the transportation of hazardous materials. These requirements ensure that the containers are safe for transportation and storage, minimizing the risk of accidents or leaks that could harm people or the environment. Meeting DOT requirements is crucial to ensure compliance with the law and maintain the safety of the transportation industry.
48.
Approved refillable tanks should never be filled to more than __ of their total capacity.
Correct Answer
C. 80%
Explanation
Approved refillable tanks should never be filled to more than 80% of their total capacity because leaving some empty space allows for the expansion of the gas inside the tank due to temperature changes. Overfilling the tank can lead to dangerous situations such as leaks or explosions. By keeping the tank at 80% capacity, there is enough room for the gas to expand without causing any harm.
49.
The ozone layer absorbs and scatters __ light from the sun, which prevents harmful amounts from reaching the earth.
Correct Answer
A. Ultraviolet
Explanation
The ozone layer absorbs and scatters ultraviolet light from the sun, which prevents harmful amounts from reaching the earth. Ultraviolet light is a type of electromagnetic radiation that has a shorter wavelength and higher energy than visible light. It can cause damage to living organisms, including humans, such as sunburns, skin cancer, and damage to the eyes. The ozone layer acts as a protective shield, absorbing and scattering the majority of the ultraviolet light, thus reducing its harmful effects on the earth's surface.
50.
Ozone at ground level is __ .
Correct Answer
A. A harmful pollutant
Explanation
Ozone at ground level is a harmful pollutant because it is formed through the reaction of sunlight with pollutants such as nitrogen oxides and volatile organic compounds. This type of ozone, known as tropospheric or ground-level ozone, can cause respiratory issues, aggravate asthma, and contribute to the formation of smog. It is different from the ozone layer in the stratosphere, which is a protective shield that absorbs harmful ultraviolet (UV) radiation from the sun.