Pollutants from Burning Fuels
Burning a fuel gives out more than carbon dioxide and water. Incomplete combustion produces carbon monoxide and soot, and sulfur and nitrogen end up as acidic or irritant gases.
What a learner can do afterwards
- Names the products of complete and incomplete combustion and states the harm each one does
- Explains where sulfur dioxide comes from and how it ends up as acid rain
- Explains why nitrogen oxides form in an engine when nitrogen is normally unreactive
- Evaluates one measure that cuts a named pollutant and says what it costs
1 · Read
Complete combustion in plenty of oxygen gives carbon dioxide and water. Starve the flame of oxygen and you get incomplete combustion instead: carbon monoxide and soot, plus unburned fuel. Carbon monoxide is a colourless killer that hijacks the blood, so a faulty heater is dangerous even when its flame looks fine.
Fuels often hold sulfur impurities, and burning turns them into sulfur dioxide. That gas dissolves into rain, which then falls acidic on forests and lakes. Stonework crumbles, fish vanish and soils sour. This acid rain can travel far past the chimney that caused it.
Engines make nitrogen oxides, even though nitrogen is normally unreactive. The extreme heat inside fuses nitrogen and oxygen from the air together. Those oxides feed smog that stings eyes and chests, and they add to acid rain. Still weather makes it all worse near roads.
Each pollutant has a countermeasure with a cost. Catalytic converters tame exhaust gases, scrubbers strip sulfur at power plants, and low sulfur fuels help too. All of them cost money and energy to build and run. Cutting pollution always has a bill attached.
Short oxygen makes CO and soot, sulfur and engine heat make acid gases, and cleanup always costs.
2 · Watch
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Where it sits
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.