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Many power stations burn coal containing sulfur.

The sulfur reacts with oxygen and produces acidic sulfur oxides.

5.7 Acid rain

What causes acid rain?

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Cars and lorry engines produce nitrogen oxides.

5.7 Acid rain

But what happens to the nitrogen and sulfur oxides produced by these processes?

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Sulfur and nitrogen oxides react with water and oxygen in the atmosphere. This forms sulfuric acid and nitric acid.

These fall to Earth as acid rain.

5.7 Acid rain

What causes acid rain?

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Fish can die when the pH of the lake they live in becomes too low.

Trees and lakes are badly affected.

5.7 Acid rain

What problems can acid rain cause?

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… and reacts with limestone in buildings and statues to wear

the limestone away.

Acid rain increases the corrosion of metals…

5.7 Acid rain