How do CFCs destroy ozone layer?
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.
How was the ozone layer destroyed?
Chlorofluorocarbons (CFCs) have been identified as the main cause of the destruction to the ozone layer, but there are also compounds containing bromine, other halogen compounds and also nitrogen oxides which cause damage. CFCs are very stable, they decay slowly and so endure in the atmosphere for up to a century.
What was destroyed by the CFCs?
Chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and halons destroy the earth’s protective ozone layer, which shields the earth from harmful ultraviolet (UV-B) rays generated from the sun. CFCs and HCFCs also warm the lower atmosphere of the earth, changing global climate.
What are CFCs and what is their role in ozone depletion?
Chlorofluorocarbons (CFCs) and other halogenated ozone-depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion. The chlorine atoms act as a catalyst, and each can break down tens of thousands of ozone molecules before being removed from the stratosphere.
How do Chlorofluorocarbons CFCs contribute to ozone depletion Brainly?
When ultraviolet light waves (UV) strike CFC* (CFCl3) molecules in the upper atmosphere, a carbon-chlorine bond breaks, producing a chlorine (Cl) atom. The chlorine atom then reacts with an ozone (O3) molecule breaking it apart and so destroying the ozone.
What is the formula of chlorofluorocarbon?
Numbering system
| hidePrincipal CFCs | ||
|---|---|---|
| Systematic name | Common/trivial name(s), code | Formula |
| Trichlorofluoromethane | Freon-11, R-11, CFC-11 | CCl3F |
| Dichlorodifluoromethane | Freon-12, R-12, CFC-12 | CCl2F2 |
| Chlorotrifluoromethane | Freon-13, R-13, CFC-13 | CClF3 |
Which of the following depletes ozone layer?
NO and freons are responsible for ozone layer depletion.
What thins the ozone layer?
The ozone layer is getting thinner. Chemicals called chlorofluorocarbons (CFCs) are a reason we have a thinning ozone layer. A chlorofluorocarbon (CFC) is a molecule that contains the elements carbon, chlorine, and fluorine.
How are CFCs disposed of?
There’s no technical hurdle to overcome to dispose of CFCs. The gas can be incinerated in special kilns, breaking the molecules into a benign mixture.
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.
Which gas is destroying 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.
Which gas is responsible for ozone layer depletion around Earth?
chlorofluorocarbons (CFCs)
Ozone depletion occurs when chlorofluorocarbons (CFCs) and halons—gases formerly found in aerosol spray cans and refrigerants—are released into the atmosphere (see details below).
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 causes chlorine to enter the stratosphere?
increased formation of ground-level ozone (smog) Most stratospheric ozone depletion is caused when chlorine or bromine reacts with ozone. Most of the chlorine entering the stratosphere is from man-made sources (84%), such as CFCs and HCFCs with the remaining 16% from natural sources, such as the ocean and volcanoes.
How are man-made compounds destroying the ozone layer?
Ozone depletion. Man-made compounds such as chlorofluorocarbons (CFCs), hydrofluorocarbons (HCFCs) and halons destroy ozone in the upper atmosphere (stratosphere). The stratospheric ozone layer makes life possible by shielding the earth from harmful ultraviolet (UV-B) rays generated from the sun.
Why was there a hearing on chlorofluorocarbons in 1981?
The July 23, 1981 hearing record includes the testimony of 22 witnesses and six statements. The purpose of the hearing was to bring the Committee up to date on research inquiries into the effects of chlorofluorocarbons on the ozone layer and the effect on humans of increased ultraviolet radiation before taking regulatory action.