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Experiments at school

Experiments für pupils at primary schools

Deutsche Version

The experiments listed below are in part abridged test arrangements of my internship experiments, a few simple experiments come from Internet sources. They were / are successfully conducted in pre-scientific project days in elementary schools.

1. Oxidation of Luminol - observation of chemiluminescence
Luminol is oxidized with hydrogen peroxide and potassium hexacyanoferrate. In this experiment a beautiful yellow-green chemiluminescence is observed. The presence and importance in nature (bioluminescence) and as emergency lights will be discussed.
Full description and experimental instruction
chemiluminescence experiments are carried out in "Chemical Laboratory for Students of Biology".

2. The dyes of green leaves are separated by chromatography
Green leaves are triturated with sand and acetone and the dyes isolated as dark green extract. This is separated into its components by thin layer chromatography (carotene, chlorophyll and xanthophylls). The appearance of these colors in the colorful autumn coloring of leaves is discussed.
A detailed experiment (incl. column chromatographic separation) is performed in the "Chemcial Laboratory for Students of Biology" durchgeführt.

3. Proof of the colored oxidation steps and formation of oxygen gas by reducing permanganate
The sugar from jelly babies reduces in alkaline solution potassium permanganate. Here, first unstable green manganese (VI) ions are formed which react further to the stable brown manganese (IV) dioxide (pyrolusite). After acidification and addition of a few drops of hydrogen peroxide, the colorless manganese (II) ion is formed. Oxygen is evolved in a violent reaction, which is detected with a smoldering wooden stick.
Similar oxidation experiments are described in the "Chemical Laboratory for Students of Biology" durchgeführt.

4. Neutralization of acids and alkalis
Acids such as hydrochloric acid can be neutralized with alkalis such as sodium hydroxide solution (and vice versa). The expiry of the neutralization is observed with the indicator phenolphthalein, which is colored strong pink in alkalis.
Similar neutralization experiments are described in the "Chemical Laboratory for Students of Biology" durchgeführt.

5. The colors of markers are analyzed by chromatography
The colors of markers are shown to be mixed together from different dyes. These colors can be separated by thin layer chromatography in the individual shades.
This experiment is described in a similar form at several sites on the Internet

6. Sodium bicarbonate and acids fill a balloon with carbon dioxide - this is then used as fire extinguishers
Baking soda (or sodium bicarbonate) is placed in an Erlenmeyer flask, then vinegar (acetic acid) is added and a balloon is evert over the neck of the flask. After a short time the balloon is filled with carbon dioxide gas by itself. Carbon dioxide is an invisible gas that is heavier than air. We use this property to delete a candle flame, by deflating the balloon in a beaker glass and the resulting carbon dioxide gas decanting in a beaker glass containing a burning candle. The dangers of carbon dioxide-filled spaces, especially in the rural area (silos) are discussed.
This experimental design is a combination and adaption of several experiments, which are described on the Internet.

7. The Bernoulli effect with a hairdryer and a ping-pong ball
A ping pong ball is not blown away by the air stream of a hairdryer, but drawn by reducing the pressure in the air flow and held in position. This effect occurs even while flying, and is discussed, for example, because of its dangers by passing trains in railway stations.
This experiment is described in a similar form at several sites on the Internet

8. A detergent (surfactant) as an engine for motor boat
A boat made of paper is placed in a water-filled bowl on the water. With the addition of a drop of detergent, the boat leaves by reducing the surface tension as if by magic pushed. This effect is discussed because of its effects on the aquatic environment.
This experiment is described in a similar form at several sites on the Internet