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Sulfur Dioxide. Properties. formula SO 2 colourless gassoluble in water melting point -72.7 °C boiling point -10 °C. Structure. bent molecule s ulfur atom has an oxidation stat ion of +4. bent - lomený. Structure. sulfur atom is surrounded by 5 electron pairs
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Properties • formula SO2 • colourless gassoluble in water • melting point -72.7 °C • boiling point -10 °C
Structure • bent molecule • sulfur atom has an oxidation station of +4 • bent - lomený
Structure • sulfur atom is surrounded by 5 electron pairs hypervalent molecule • most of valence electrons are engaged in S-O bonding.
Natural Sources • oceans • volcanoes • forest fires
Man – made Sources • fossil fuel combustion • smelting • manufacture of sulphuric acid • conversion of wood pulp to paper • combustion – spalování • wood pulp – dřevní buničina
Man – made Sources • production of elemental sulphur • coal burning • oil burning
Production and Reaction S8 (l) + 8 O2 (g) → 8 SO2 (g) Burning sulphur to give a blue flame • constituent - základní
Production and Reaction Cu (s) + 2 H2SO4 (aq) → CuSO4 (aq) + SO2 (g) + 2 H2O (l)
Production and Reaction SO2 (g) → SO2 (aq) SO2 (aq) + H2O (l) → H2SO3 (aq) • demonstrate - ukázat • container - nádoba
Production and Reaction NaHSO3 (aq) + H2SO4 (aq) → NaHSO4 (aq) + H2O (l) + SO2 (g) • drip - nakapat
Uses As a preservative • for dried apricots and other dried fruits • to maintain their appearance • to prevent their rotting • apricot - meruňka • appearance - vzhled • rotting - hnití
Uses In winemaking • as an antibiotic and antioxidant to protect wine from spoilage by bacteria and oxidation • to keep volatile acidity • in winery sanitation • spoilage – zkažení • winery sanitation – hygiena vinice
Uses Biochemical and biomedical roles • blocks nerve signals from the pulmonary stretch receptors • abolishes the Hering-Breuer inflation reflex • pulmonary – plícní • abolish - zrušit
Health Impacts • can affect the respiratory system, the functions of the lungs coughing, asthma and chronic bronchitis • affect – postihnout • impact – dopad • prone - náchylný
Environmental Impacts Acid rain • damages trees, crops, historic buildings and monuments • makes soils, lakes and streams acidic • is a term used to describe all forms of acid precipitation (rain, snow, hail, fog, etc.) • crop – úroda • hail - krupobití • soil – půda • precipitation - srážka
Environmental Impacts • precipitation is naturally acidic because of carbon dioxide in the atmosphere. The burning of fossil fuels (coal, oil and gas) produces sulphur dioxide and nitrogen oxides which can increase the acidity of rain or other precipitation
Environmental Impacts • the increasing demand for electricity and the rise in the number of motor vehicles in recent decades has meant that emissions of acidifying pollutants have increased dramatically from human sources, particularly since the 1950‘s • demand – požadavek • pollutant – znečisťující látka
What We Should Do ??? • to reduce our dependence on fossil fuels and energy consumption • not driving around, flying and having the heating or air conditioning turned up so high • dependence - závislost • consumption - spotřeba
What We Should Do ??? If we’re cold, just wear more clothes
What We Should Do ??? • don‘t be lazy and use your own energy to do things like cycling, walking and running
What We Should Do ??? • find out more about renewable energy like solar power
What We Should Do ??? • find out more about renewable energy like hydroelectric power
What We Should Do ??? • find out more about renewable energy like wind power
AND REMEMBER !!! How you choose to use energy affects all life on Earth so think before you act.
Sources of Information • http://en.wikipedia.org/wiki/Sulfur_dioxide • http://www.epa.gov/air/urbanair/so2/ • http://so2.umbc.edu/omi/ • http://www.chm.bris.ac.uk/motm/so2/ so2h.htm • http://mattson.creighton.edu/SO2/ SO2_Info.html