Page 103 - ICSE Science 3 : E-book

• Observe the changes in water level of each cup every hour and mark it using the
marker.

Observation:
You will observe that water level in the covered cup remains the same or decreases
only a little as the evaporation is blocked by the foil. The water level in the uncovered

cup decreases. The sun’s heat causes its water to change into water vapour and
evaporate.

Result:
This shows that water evaporates when the temperature is increased.

ACTIVITY TIME

Decrease in Temperature Causes Condensation

Aim:
To study and understand that water condenses when temperature is reduced

You Need:

A glass, hot water, a ceramic plate and ice cubes

What to Do:
• Fill half the glass with hot water.

• Place the ceramic plate on it.
• Then put ice cubes in the ceramic plate and
observe what happens.

Observations:

You will observe tiny droplets of water forming on the lower surface of the ceramic
plate. These water droplets form because water evaporates in the form of vapour and
then cools down on touching the cold surface of the plate. Finally, it condenses to form
water again.

Result:
This shows that water condenses when the temperature is decreased.

Water keeps on changing its form continuously in nature through evaporation and
condensation. The water cycle is the way through which water moves all around
the earth.

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