Page 170 - ICSE Chemistry 8

• Water present in rivers, lakes, streams and ponds is freshwater. It comes from mel ng of snow on
mountains and from rain. Along its course, it becomes impure as it travels through hills and plains.
This water has to be purifi ed in order to make it free from various impuri es.

Groundwater

Rainwater falling on the earth’s surface seeps down and gets accumulated under the ground. The water
so collected under the ground is called groundwater. The level of water under the ground is called water
table. Water table varies according to the place and season.

Natural springs contain groundwater. Groundwater can also be obtained from wells, tube wells and
handpumps. It does not contain any impuri es as it gets fi ltered while passing through diff erent layers of
rocks and sand.

ocean lake well

spring tube well handpump

Fig. 8.3: Some sources of water

Activity 8.1

Aim: To show that rainwater does not contain any dissolved
impuri es, but well water has impuri es
Materials required: Two porcelain dishes, two beakers
containing water, a sample of rain water, a sample of well water,
two burners
Procedure

• Take samples of rainwater and well water in two porcelain dishes.
• Keep the porcelain dishes over two beakers containing water.
• Heat the beakers ll the water in the porcelain dishes evaporates.

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