Acid rain formation and control

Tropospheric ozone

Primary pollutant; increases impact of acidic gases

Peroxy acetyl nitrates (PANs)

Combination of pollutants; form when pollutants combine

Primary pollutant

Directly emitted into the atmosphere

Secondary pollutant

Formed by reaction of primary pollutants

Acid rain pH

Naturally slightly acidic (5.6); more acidic due to pollution

Sulphurous acid

SO2 dissolves to produce; involved in acid rain

Sulfuric acid

SO3 dissolves to produce; stronger acid in acid rain

Hydrogen chloride

Produced from fossil fuel combustion; contributes to acid rain

Nitrous and nitric acids

Formed from NOx dissolving in water; contribute to acid rain

Desulfurization

Process to remove sulfur from fuel before burning

Flue-gas desulfurization (FGD)

Removal of SO2 from power station emissions after combustion

Dry flue-gas desulfurization

Method using CaCO3 to react with SO2; produces calcium sulfate

Wet flue-gas desulfurization

Method using sodium sulphite solution to scrub gases

Catalytic converters

Reduces NOx back to O and N; control oxides of nitrogen

Urea sprays

React with NOx to reduce emissions; control oxides of nitrogen

Carbon monoxide (CO)

Odourless gas from incomplete combustion; binds to haemoglobin

Statistical test for data analysis

Recommended based on data characteristics and hypothesis

Sulfur dioxide emission decrease

Calculation of percentage reduction over a specific time period

Gypsum building plaster

Product made from clean calcium sulfate

Low temperature combustion

Method to reduce NOx emissions

Environmental factors affecting severity

Variables influencing the impact of acid rain

Control measures for carbon monoxide

Methods to convert CO to less harmful compoundsTropospheric ozone