Page 81 - Active Science 5 Ebook and Activity

Thermometer

Condenser
Distillation
flask

Salty water Cooling
water out Cooling
water in
Heat
Distillate
(pure water)

• Set the stand so that it firmly holds the flask in place, supported by
the tripod stand.
• Place the burner below this apparatus.
• Connect the pout of the distilling flask to one end of the condenser.

• Set the condenser with the help of its stand so that it slopes a little
downward. Its pout (other end) must open directly above the beaker.
• Bring the salty water to a boil and collect the condensed liquid for
observation.
Observation : When impure water is heated, it starts boiling and steam is formed.
Steam rises up and enters the beaker, cooling arrangement, only to
change back into water. This water is free of impurities as these are
left behind in the distillation flask. Pure water is collected in the
collector as distillate.

Conclusion : The condensed liquid that gets collected in the beaker is clear as well
as tasteless and odourless. Therefore, pure and clear water can be
obtained from an impure solution by simple distillation.

Activity 6.9

Why is water said to be a ‘very good solvent’? Find out any five things which dissolve in water
completely. Also write five things which partially dissolve in water.

Removing Germs from Water

Removal of germs and various harmful substances from water makes it fit for drinking.
Drinking water supplied to our homes is unfit for drinking and therefore, it is treated
first. Boiling, adding chlorine tablets and using UV filters are some methods used to

purify water at home.
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