User Manual

Trouble shooting
If only a little clear water is collected, check that the water is hot enough. Only hot water with
steam rising from it will generate enough vapour to demonstrate distillation. Empty the water
in the set up and redo the experiment with hot water.
Where we use distillation
Distillation is used to clean drinking water and for making sterile water for medical use and for
cleaning contact lenses. It is also used in desalination plants, where fresh water for drinking
is made from sea water. In chemistry, distillation is used to remove water from a liquid without
losing the water. And in the oil industry, distillation is used to separate crude oil into different
products, such as butane gas, petroleum and fuel oil. In those distillation plants, the liquid to
be distilled will be heated to generate the vapour for completing the process.
Demonstrating the water cycle
You can use the same equipment to investigate the Earth’s water cycle.
For this you will also need a tall transparent glass whose diameter is
smaller than the collector (or ask an adult to cut the top third off a
small plastic bottle), some soil and a small plant, such as an ivy.
1. Put a few centimetres of soil into the base of the glass. Make
a hole in the soil, gently push in your plant and press the soil
around its roots. Pour a little water into the soil.
2. Put the collector and cup over the glass. (If you are using a
bottle base, make sure the rim of the bottle fits closely under
the collector, otherwise water vapour will escape through the
gap. You may need to seal the gap with sticky tape.)
3. Put the cup in a sunny place and wait a few hours. Look at
the underside of the collector. You should see condensation,
and water should eventually run into the small cup.
This experiment is a model of the water cycle. Water evaporates
from the soil and the plant, as it does in nature, because of heat
from the Sun. The condensation on the collector represents the
formation of clouds, and the dripping water represents rain.
Fun facts
• The distillation equipment in this kit is known as a “still”.
• A solar still is powered by the Sun and used to purify water in hot countries. The Sun’s heat
makes the water evaporate, and cool air makes it condense again.
• The water cycle is the constant circulation of water between the oceans, the atmosphere and
the land. It makes clouds and rain form, and rivers flow.
Condensation
Clear
Water
D. EXPERIMENT 2 - DISTILLATION
Warning: This experiment requires hot water. Adult assistance and supervision is required when
handling hot water.
In this experiment you purify water by a process called distillation. The water evaporates,
leaving the impurities behind. Distillation is another common method of producing clean
water. The method is commonly used in desalination plants.
You will need: funnel-shaped collector, small plastic cup.
Also needed (but not included in the kit): a glass of hot water (hot enough to be steaming),
ice cubes, and some tea leaves.
Doing the experiment
1. Ask an adult to help you with this step. Prepare a glass steaming of hot water. Mix it with
the tea leaves.
2. Push the base of the collector into the cylinder in the centre of the cup. Place the collector
on top of the glass containing the tea.
3. Drop some ice cubes into the collector.
4. After a while, look at the underside of the collector. You should soon see condensation.
Eventually drops of clear water will run down and drop into the cup.
How it works
Water evaporates from the surface of the hot tea. This means the liquid water turns to water
vapour (the gas form of water). However, neither the tea leaves nor the chemicals they release
into the water evaporate. The ice makes the collector cold. When the water vapour hits the
collector, it cools and condenses (turns back to liquid water). Then it drips into the cup. So
the process of evaporation and then condensation, which is known as distillation, removes
impurities (the tea leaves and chemicals in this experiment) from the water.
1 2 3 4
Ice cubes
Hot tea
Hot water
Tea
leaves
6 7
Clear Water
Condensation
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