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Question
How can you obtain pure water from a salt-water mixture (or salt-solution) ? Draw a neat and labelled diagram of the apparatus you would use to obtain pure water from a salt-water mixture (or salt-solution).
Solution
We can obtain pure water from a saltwater mixture (or salt solution) by the process of distillation. Important steps underlying the process are as follows:
The salt water mixture is taken in a distillation flask and heated subsequently.
On heating, water vapours are formed that rise up and come through the side tube B.
It is then passed through condenser C.
Cold water from the tap is circulated in the outer tube of the condenser, so that the hot vapours are cooled.
The vapours condense and are collected in another beaker.
This pure water is called distilled water.
Salt, being non-volatile, remains in the flask and can be obtained later.
Separation by distillation. Here a mixture of salt and water (or salt-solution) is being separated by distillation.
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