What you’ll learn9 learning objectivesChoose one objective for a focused lesson, or study the complete topic.10.3.1Composition of clean, dry air as• State the composition of clean, dry air as approximately 78% nitrogen, N2, 21% oxygen, O2 and the remainder as a mixture of noble gases and carbon dioxide, CO2Syllabus objective10.3.2Air pollutant sources: CO2 from• State air pollutant sources: CO2 from complete combustion; CO/particulates from incomplete combustion; methane from decomposing vegetation and animal digestion; nitrogen oxides from car engines; sulfur dioxide from sulfur-containing fossil fuelsSyllabus objective10.3.3Pollutant effects: CO2 and methane• State pollutant effects: CO2 and methane increase global warming/climate change; CO is toxic; particulates increase respiratory/cancer risk; nitrogen oxides cause acid rain, photochemical smog and respiratory problems; sulfur dioxide causes acid rainSyllabus objective10.3.7Greenhouse gases carbon dioxide and• Describe how the greenhouse gases carbon dioxide and methane cause global warming, (a) the absorption, reflection and emission of thermal energy (b) reducing thermal energy loss to spaceSyllabus objective10.3.4Reduction strategies: for climate• Explain reduction strategies: for climate change, plant trees, reduce livestock, use less fossil fuel, increase hydrogen/renewables; for acid rain, use catalytic converters, low-sulfur fuels and flue gas desulfurisation with calcium oxideSyllabus objective10.3.5Photosynthesis as the reaction between• Describe photosynthesis as the reaction between carbon dioxide and water to produce glucose and oxygen in the presence of chlorophyll and using energy from lightSyllabus objective10.3.6Word equation for photosynthesis• State the word equation for photosynthesis, carbon dioxide + water → glucose + oxygenSyllabus objective10.3.8How oxides of nitrogen form in car• Explain how oxides of nitrogen form in car engines and describe their removal by catalytic converters, e.g. 2CO + 2NO → 2CO2 + N2Syllabus objective10.3.9Symbol equation for photosynthesis• State the symbol equation for photosynthesis, 6CO2 + 6H2O → C6H12O6 + 6O2Syllabus objective