Acid Rain OCR Chem B

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Causes of Acid Rain

The burning of fossil fuels also produces nitrous oxides and sulfur dioxides

These dissolve in water vapour in the atmosphere and react with water to form acids

This water vapour condenses into clouds and will then fall as acid rain

Oxides of nitrogen + water → Nitric acid

Sulfur dioxide + Water → Sulfuric acid

The high temperature inside an internal combustion engine allows nitrogen from the air to react with oxygen to make oxides of nitrogen. These gases irritate the lungs and cause acid rain.

Catalytic converters remove carbon monoxide from exhaust fumes according to the following equation:

2CO+2NO→N2+2CO22CO+2NO→N2+2CO2

2CO + 2NO \rightarrow N_2 + 2CO_2

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Harms of Acid Rain and other Atmospheric Pollution

Acid rain:

Increases the rate of weathering - Damaging buildings made of limestone or marble

Increases the rate of corrosion of metals

Makes soil acidic - Some crops find it hard to grow

Makes lakes acidic - Prevent fish eggs hatching

Kills fish and insects - Especially conifer trees

Nitrous oxides:

Cause respiratory diseases - Such as bronchitis

Cause smog - When they react with other chemicals in the presence of sunlight

Incomplete combustion of fossil fuels:

Releases carbon monoxide - Which reduces the amount of oxygen the blood can carry

Releases particulate carbon - Which settles on objects and makes them dirty