Acid Rain

Pollution from power stations and car exhausts can release other harmful gases into the air as well as carbon dioxide. These gases can be carried long distances by the wind before they are dissolved by raindrops to form "acid rain". When this falls to Earth, it’s acidity causes it to slowly eat away at buildings, as well as killing trees, plants and life in rivers and lakes.

Do you know if rain in your area is acidic? You can follow the instructions below to find out.

Test for Acid Rain

You will need:

• 2 red cabbage leaves – finely chopped
• distilled water (available from chemists)
• rainwater (collected from your garden)
• a bowl
• 2 glass jars
• a measuring jug
• a sieve

Place the chopped cabbage leaves into the bowl. With the help of an adult, pour hot distilled water over them, and let it stand for an hour.

Use the sieve to strain the liquid from the cabbage leaves into a measuring jug. It should be a dark purple colour.

Using the measuring jug, pour 20ml of distilled water into one of the glass jars. Pour 20ml of rainwater into the other.

Now add some of the cabbage juice into the two jars – making sure you put the same amount in each. The water will then change colour.

How does the colour of the water in the two jars compare? You should find that the distilled water stays the same, whereas the rainwater may change colour. It will turn red if the rainwater is acidic; the stronger the acid, the redder the water will become.

You have now completed the Weather Features section.  If you are interested in using some of the knowledge and skills you have just acquired, then click on the sunshine icon to go to the Activities section.  There you will find projects and games related to The Changing Climate, as well as other areas of meteorology.  Otherwise it is possible to return to the Weather Features homepage to select any topics you may have missed out on!