Maintaining Air Quality

• air cooled & compressed into liquid • liquid separated into fractions by frac distillation in fractionating column • gases separated due to diffs in bp, n2 (lowest bp) distilled at top

• incomplete combustion of c-containing fuels/petrol 1. reacts w/ haemoglobin in blood to form carboxyhaemoglobin, reduce ability to transport o2 2. cause headache, fatigue, breathing difficulty, death

• combustion of sulfur-containing fuels/fossil fuels • emission from volcanic eruption 1. irritates eyes & lungs, cause breathing difficulties 2. high levels -> lung inflammation (bronchitis) 3. reacts w/ h2o to form rain water, corrodes metal structures & limestone buildings, harms aquatic life & plants • so2 dissolve in h2o -> sulfurous acid • sulfurous acid oxidise in air -> sulfuric acid

• nitrogen reacting w/ o2 at HIGH TEMPS, during lightning activity & in car engines 1. irritates eyes & lungs, cause breathing difficulties 2. high levels -> lung inflammation (bronchitis) 3. NO2 ONLY - reacts w/ h2o to form rain water, corrodes metal structures & limestone buildings, harms aquatic life & plants (nitric acid)

• released in vehicle exhaust fumes & chemical plants 1. cause cancer (carcinogenic) 2. reacts w/ no in presence of sunlight to form toxic ozone

• ozone pollutant @ atmosphere, layer protection against uv light @ stratosphere UV CAUSES: 1. skin cancer 2. genetic mutation 3. eye damage CHLOROFLUOROCARBONS (CFCs) - main cause damage, made of C, F, Cl 1. found in aerosol cans, fridges, air-con, plastic foam 2. decompose in UV light to form highly reactive Cl atoms 3. highly reactive Cl react w/ ozone molecules to form Cl oxide & o2, destroying ozone

• decay of plant & animal matter 1. greenhouse gas, traps heat in atmosphere, global warming 2. leads to droughts/floods in low-lying lands due to melting of polar ice caps

• in cars, convert CO, NOx, unburnt hydrocarbons into harmless substances • honeycomb structure: large surface area volume ratio

• photosynthesis • respiration • combustion of fuels

• calcium carbonate/oxide reacts w/ so2 to form calcium sulfite (CaSO3) • o2 from air oxidises calcium sulfite to calcium sulfate (CaSO4)

cos & h2o retain heat, maintain surface temp - buildup co2, methane, n2o lead to global warming, temp RISES - effects: unusual weather conditions (hurricanes, droughts, tsunamis), melting polar ice caps (floods)