History of CFCs
This mechanical engineer and chemist synthesized the first chlorofluorocarbon in 1928
Who is Thomas Midgley Jr.?
Because they do not easily catch fire or cause poisoning, CFCs were originally heavily marketed as having these two critical safety features.
What are non-toxic and non-flammable
This mechanical part of the refrigerator compresses the coolant gas, forcing it to release heat during the pressure increase.
What is the compressor?
The planet's protective ozone layer is found entirely within this specific level of the Earth's atmosphere.
What is the stratosphere?
This specific halogen element is released directly into the stratosphere when incoming ultraviolet rays break apart CFC molecules.
What is chlorine?
Midgley developed his groundbreaking chemical alternative while working for this major automotive manufacturing corporation
What is General Motors?
CFCs possess this physical property, meaning they feature a low boiling point and transform into vapor with ease.
What is volatile?
In this component of the refrigerator, compressed gas sheds heat and undergoes a phase change into a liquid state.
What are condenser coils?
Ozone acts as an environmental shield by directly absorbing and blocking these two harmful subclasses of solar ultraviolet radiation.
What are UV-B and UV-C rays?
The severe geographic atmospheric depletion known as the ozone hole forms exclusively over this continent.
What is Antarctica?
This was the commercial trade name given to dichlorodifluoromethane, the first widely implemented CFC coolant.
What is Freon-12?
Aside from ozone damage, CFCs act as this type of atmospheric hazard by directly trapping infrared light.
What is a greenhouse gas?
The actual chilling effect inside the appliance happens here, where liquid coolant evaporates to absorb heat from the fridge interior.
What are evaporator coils?
In natural ozone formation, a single free oxygen atom must chemically merge with this specific molecule to yield O3.
What is O2?
Due to unique atmospheric conditions, the localized destruction of the ozone layer reaches its peak during these specific months of the year.
What are August through October?
Refrigerators in the late 1800s and early 1900s relied on toxic options like sulfur dioxide, ammonia, and this compound, which caused fatal leaks in the 1920s.
What is methyl chloride?
The slide presentation notes four specific chemical variants of CFCs, including CFC-11, CFC-12, CFC-113, and this fourth numerical formula structure.
What is CFC-111?
In an aerosol delivery system, the compressed liquid propellant is completely blocked from expanding into a gas until this mechanical part is actuated.
What is the valve?
Natural ozone destruction happens when UV rays split O3 apart into O2 and this other component.
What is a free oxygen atom?
Scientists officially define the boundary of the ozone hole when concentrations drop below this specific numeric baseline.
What is 220 Dobson units?
In 1987, this airborne research operation flew a high-altitude aircraft out of Punta Arenas to gather definitive proof connecting CFCs to atmospheric damage.
What is the Antarctic Airborne Ozone Expedition?
CFCs remain incredibly resilient in the lower atmosphere because they possess this specific chemical property, keeping them from breaking down easily.
What is stable?
Inside a pressurized spray can, the liquid coolant propellant must thoroughly blend with this internal substance before deployment.
What is the concentrate?
When a chlorine monoxide molecule reacts with a free oxygen atom, it forms an oxygen molecule and regenerates this catalyst.
What is chlorine?
In 1985, scientific consensus shifted rapidly when the first formal academic paper documenting springtime ozone depletion was officially published by researchers from this long-running observatory.
What is the Halley Bay Observatory?