c c c c . c c . . c . c . c . c 2. c

E 11111111. Set-up for burner

11 2. burning

3. Set-up for extinguishing and testing

14. Collecting products 1

1E 1115. Testing for CO2

Assembling, burning, extinguishing, testing products of combustion

In a previous experiment a high no-cost ampoule (5 ml) was used as part of a pipette eudiometer. In the following experiment a safe micro spirit burner will be assembled from a low-cost ampoule (2 ml) that can be tightly stored in a film canister (Photo 1). A broad no-cost ampoule (5 ml) is taken to extinguish the flame and to collec the combustion gases (water, carbon dioxide).

Material
Tray, container for waste, 3 ampoules (2 ml, 5 ml high, 5 ml broad) with stoppers, stopper of an infusion bottle (stand), scissors, piece of toilette paper, Leukosilk for labels, permanent marker, plastic dropper bottle with methylated spirit, lime water, matches.
Procedure
1. Fix an ampoule (2 ml) in the stopper of an infusion bottle. Label it with an F (flamable). Fill it with methylated spirit. Place it inside the tray.
2. Cut a 3 cm stripe of toilet paper, roll a wick from it, completely dip it into the ampoule with methylated spirit.
3. Lit the burner (Photo 2), cover the flame with the broad ampoule (Photo 3, 4).
4. Stopper it. Look for condensed water. Add drops of lime water, shake, look for its changes (Photo 5).
Observations
a) Methylated spirit climbs up in the wick. It burns with a blue flame, that is yellow at the end (Photo 2).
b) As soon as the flame is covered by the ampoule it goes out.
c) Tiny drop of a condensed colourless liquid appear inside the ampoule walls.
d) The lime water becomes white and milky (Photo 5).

Explanation
a) The fuel is climbing to the top of the wick due to capillary forces. The blue colour of the flame is due to burning carbon monoxide. The yellow flame colour indicates carbon particles.h
b) The flame is extinguished because oxygen is consumed and carbon dioxide is released.
c, d) In an exothermic reaction ethanol of the methylated spirit and oxygen of the air react. Water and carbon dioxide are formed.

Addition
Try to lit a short stripe of magnesium above the top of the flame. Cut, fold and glue a pyramidal periodic table of elements to explain the reaction.
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first publication: 10.10.2008 l..l...last modification: 05.11.2008 l..l..l. back

pipette eudiometer to explode oxyhydrogen gas. second period: pipette experiments with 20 mg samples of calcium and calcium carbide. ..... 

 

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