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When air is consumed it needs less space

What you need: Glass bowl (0.5 L), metal stand (e.g. 3 ring magnets), micro spirit burner, water glas (0.2 L). This experiment is for adults, it can also be done with a candle in a soup plate.
Fill the bowl with water, place the metal stand into it and put the burner on it.
Left and photo 2: Put the glass above the burner, just dip it into the water.
Observation: The flame fades. Photo 3: The flame goes out.
Photos 3  and 4: The water rises up to the rim of the burner.
Right: The burner is placed aside the water glass and a 15-cm ruler.
Explanation: The spirit burner needs air for burning. Part of the air locked up inside the glass is consumed during combustion. So water is sucked up into the glass.

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