Table of Contents
What gas is released by CFCs?
Chlorine
Chlorine released from CFCs destroys ozone in catalytic reactions where 100,000 molecules of ozone can be destroyed per chlorine atom. A large springtime depletion of stratospheric ozone was getting worse each following year.
What are destroyed by CFCs?
Chlorofluorocarbons (CFCs) are a class of chemical refrigerants that destroy the ozone layer and warm our planet. They are both ozone depleting substances (ODS) and potent greenhouse gases (GHGs).
Which chemical from CFCs destroys the ozone layer?
chlorine
Reactions on the surface of icy cloud particles release chlorine from chemical compounds like CFCs, into a form that reacts with ozone. When sunlight returns in the spring, the chlorine begins to destroy ozone.
Can CFCs be destroyed in the atmosphere?
ODS that release chlorine include chlorofluorocarbons. Since they are not destroyed in the lower atmosphere, CFCs drift into the upper atmosphere where, given suitable conditions, they break down ozone.
How are CFCs removed from the atmosphere?
These CFCs are not soluble in water, so deposition does not removed them from the air. “The only other mechanism that removes compounds from the troposphere is reaction with an abundant oxidizing agent–such as hydroxyl radicals, ozone, or nitrate radicals.
Are CFCs greenhouse gases?
While acting to destroy ozone, CFCs and HCFCs also act to trap heat in the lower atmosphere, causing the earth to warm and climate and weather to change. HFCs, CFCs and HFCs are a subset of a larger group of climate changing gases called greenhouse gases (GHGs).
How do CFCs enter the atmosphere?
CFCs reach the stratosphere because the Earth’s atmosphere is always in motion and mixes the chemicals added into it. This is because winds and other air motions mix the atmosphere to altitudes far above the top of the stratosphere much faster than molecules can settle according to their weight.
Which of the following is threat to the Ozonosphere?
Which of the following is threat to the ozonosphere? Explanation: Ozone layer within the atmosphere protects life on earth from harmful ultraviolent radiation from the sun. Chlorofluorocarbons (CFCs) that were used as refrigerants and aerosol spray propellants expose a threat to the ozonosphere.
Which one of the following is the range of Ozonosphere in atmosphere?
The correct answer is Stratosphere. The ozone layer, also called the ozonosphere, a region of the upper atmosphere, between roughly 15 and 35 km (9 and 22 miles) above Earth’s surface, containing relatively high concentrations of ozone molecules (O 3).
Why are CFCs a concern to the environment?
The environmental concern for CFCs follows from their long atmospheric lifetime (55 years for CFC-11 and 140 years for CFC-12, CCl 2 F 2) 9 which limits our ability to reduce their abundance in the atmosphere and associated future ozone loss. This resulted in the Copenhagen Amendment that further limited production and was approved later in 1992.
How are chlorofluorocarbons related to the destruction of the ozone?
Photodissociation of the chlorofluoromethanes in the stratosphere produces significant amounts of chlorine atoms, and leads to the destruction of atmospheric ozone.” From an environmental standpoint, ozone is a confusing molecule.
What happens when a CFC is broken down?
Virtually all the CFC breaks down, and the result is salt, carbon and carbon dioxide. The authors say they can also use the technique to synthesise unsaturated, ring-shaped fluorinated chemicals from the common saturated variety. The unsaturated compounds can then be used as building blocks for new chemicals.
Why are CFCs useful in the stratosphere?
CFCs are extremely inert, which is what makes them useful in industry, and long-lived enough to rise into the stratosphere where they deplete ozone. It also makes them very hard to break down chemically.