Once in the atmosphere, CFCs drift slowly upward to the stratosphere, where they are broken up by ultraviolet radiation,
releasing chlorine atoms
, which are able to destroy ozone molecules. … When sunlight returns in the spring, the chlorine begins to destroy ozone.
Why are CFCs so reactive with ozone?
But
UV light can break up a CFC
, making it highly reactive. In the lower atmosphere, CFCs are protected from UV light from the ozone layer in the stratosphere. … They release chlorine, and these free chlorine atoms rip oxygen atoms off of ozone, leaving ordinary oxygen gas.
How do CFCs react with ozone?
CFCs do not easily react with other substances. In fact, they break up only through sunlight, which divides their molecules, causing the release of chlorine (Cl). Once the chlorine is released, it is able to react with ozone (O3), to form
chlorine monoxide (ClO) and oxygen
(O2).
Why do CFCs deplete the ozone layer but HFCS do not?
Under the auspices of the Montreal Protocol treaty signed in 1987, CFCs were officially phased out of production worldwide in 2010. While HCFCs contain chlorine atoms, they are less damaging to the ozone layer
because they also contain hydrogen atoms
, which causes them to break down in the atmosphere faster.
Why do CFCs break down?
When they are exposed to strong ultraviolet light, CFCs finally break down to
release lone chlorine atoms with an unpaired electron
. These chlorine atoms are highly unstable and react with ozone to break it down into oxygen through a type of chain reaction.
What destroys the ozone layer?
Ozone Depletion. When
chlorine and bromine atoms come into contact with ozone
in the stratosphere, they destroy ozone molecules. One chlorine atom can destroy over 100,000 ozone molecules before it is removed from the stratosphere. Ozone can be destroyed more quickly than it is naturally created.
Why is ozone so reactive?
Ozone reacts directly with organic double bonds. When ozone breaks down to dioxygen, it
produces oxygen free radicals
, which are highly reactive and capable of damaging many organic molecules. Moreover, it is believed that the powerful oxidizing properties of ozone may be a contributing factor of inflammation.
Are CFCs still used?
Today,
the use of CFCs is outlawed by 197 countries around the world
and scientists concur that the ozone layer is slowly recovering as a result. Overall, the success in addressing the ozone problem can give us hope that global environmental problems can and have been solved by humanity’s timely collective action.
What are the adverse effects of ozone hole formation?
Ozone layer depletion causes
increased UV radiation levels
at the Earth’s surface, which is damaging to human health. Negative effects include increases in certain types of skin cancers, eye cataracts and immune deficiency disorders.
Are main ozone depletes?
The main uses of ozone depleting substances include:
CFCs and HCFCs in refrigerators and air conditioners
, … CFCs and HCFCs in foam, CFCs and HCFCs as aerosol propellants, and.
What are 3 causes of depletion to the ozone layer?
The main cause of ozone depletion and the ozone hole is manufactured chemicals, especially
manufactured halocarbon refrigerants, solvents, propellants, and foam- blowing agents (chlorofluorocarbons (CFCs), HCFCs, halons)
.
Is R23 ozone depleting?
The recent study focused on five types of HFCs that are expected to contribute to global warming by 2050 – R125, R143a, R134a, R32 and R23. …
Are HCFCs ozone depleting?
The HCFCs are one class of chemicals being used to replace the CFCs. They contain chlorine and thus deplete stratospheric ozone, but to a much lesser extent than CFCs. HCFCs have ozone depletion potentials (ODPs) ranging from
0.01 to 0.1
.
Why do CFCs stay in the atmosphere for so long?
CFCs reach the stratosphere because
the Earth’s atmosphere is always in motion and mixes the chemicals added into it
. … Gases such as CFCs that do not dissolve in water and that are relatively unreactive in the lower atmosphere are mixed relatively quickly and therefore reach the stratosphere regardless of their weight.
Are CFCs toxic to breathe?
Inhaling CFCs
Inhalation of CFCs can also disturb the heart rhythm, which can lead to death. Exposure to large amount of CFCs could
potentially cause asphyxiation
, according to the Centers for Disease Control and Prevention.
Is there still a hole in the ozone layer 2020?
The record-breaking
2020 Antarctic ozone hole finally closed at the end of December
after an exceptional season due to naturally occurring meteorological conditions and the continued presence of ozone depleting substances in the atmosphere.
