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19 Cards in this Set
- Front
- Back
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Structure of ozone
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2 pi bonds
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Breaking down of ozone vs. breaking down of oxygen gas (in terms of wavelengths)
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Ozone can be broken down by longer wavelengths than oxygen gas.
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Example of a hydroclorofluorocarbon
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Chlorodifluoromethane (CHF2Cl)
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Why are HClFCs only a temporary solution?
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They reduce the ozone layer due to the C - Cl bond in the molecule.
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Ozone properties
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Pale-bluish gas with a pungent odour, very reactive
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Formation of O3
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O2 + UV light ->2.O / O2 + .O -> O3
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Where is O3 located?
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In the stratosphere (15-45 km above earth's surface)
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Ozone layer is constantly:
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Formed and broken down.
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Formation of O3
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Photo-dissociation of molecular O2
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CFCs
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Found in sprays - chemically inert and contain Cl
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Ozone bonding
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O = O - O
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Nitric oxide
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(Increased temperature) NO + O3 = NO2 +O2
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How does ozone act as a shield?
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Absorbs 99% of the sun's harmful UV light.
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Ozone formula and place in atmosphere
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O3, stratosphere
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Properties of ozone (3)
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Pale bluish gas, acrid odor, very reactive (powerful oxidizing agent).
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Formation of ozone
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Photodissociation of molecular oxygen by UV light :
O2 + UV -> 2 .O / O2 + .O -> O3 |
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Ozone is being depleted by
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CFCs, nitric oxides etc.
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Alternatives for CFCs
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Hydrocarbons, hydrochlorofluocarbons, fluorocarbons, hydrofluorocarbons.
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Oxygen radicals forming O2 gas (equation)
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O3(g) + O(g) -> 2O2 (g)
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