How Is Acid Rain Formed?

Acid rain, also known as acid precipitation is formed when sulfur dioxide and nitrogen oxides are emitted into the atmosphere and undergo chemical transformations, then absorbed into clouds.

This pollution than falls from the clouds as rain, snow or sleet and increases the acidity of the soil and also affect the chemical balance of lakes and streams.

It is the action of humans that cause the bulk of acid rain – electricity generation, factories and motor vehicles create the pollution that causes the acid rain effect. The gasses that are released from all of these activities can be carried hundreds of miles before they eventually fall as acid rain, so pollution generated in the UK for example can affect other countries more than it affects this country.

It has been shown to have adverse effects on forests, freshwaters, and soil, and can kill off insect lifeforms and cause damage to buildings.

Acid rain can affect the growth of forests and cause leaves and needles to go brown and fall off and die. Whole areas of forest can die in some extreme situations.

Other plants can also be damages, but the effect on crops of offset by the use of fertilisers.

There are no proven direct links with human health although fine particles formed from the same gases as acid rain have been known to cause ill health and premature death.

Soot,carbon mono oxide, sulphur dioxide

Acid rain is usually formed by the settlement of acidic elements in rain, snow, dew or other dry particles.

The more precise expression for acid rain is "acid precipitation". Acid rain usually takes place when sulphur dioxide and nitrogen oxides are let out into the environment and later undergo chemical transformation and are sucked up along with water droplets in clouds. These droplets later fall on the surface of the earth in the form of rain, snow, mist, dry dust, hail, etc.

When these droplets mix with the soil, they amplify the acidity of the soil, in a way changing the chemical balance of lakes and streams. Acid rain also increases the weathering in carbonate rocks. When the level of acid builds up in rivers and lakes it can be harmful for fish.