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Me16f Water electrolysis 6: Smallscale-Hofmann apparatus with 2 Liquemin bottles

For a successful test of the elements of water Hofmann apparaturus für more than 5 mL electrolyte are needed. The following appliances were developed in a brain storming during a SINUS workshop. Another apparatus developed by Obendrauf  consists of two syringes with paper clip electrodes.

Material: 2 Liquemin bottles full of sodium sulfate solution, small plastic honey packing,  2 sterile hypodermic needles extracted from an 1-mL insulin syringe, 9-Volt battery, electric wire with crocodile clips, plastic pipette, goggles, candle, matches.
Experiment:
1. Pierce a small plastic honey  packing with two hypodermic needles extracted from an insulin syringe.
    Choose a distance between the needles to have space for two bottles to be put over them.
2. Cover the bottom of the packing with sodium sulfate solution.
3. Make an electric connection between the battery an the lower ends of the needles.
4. Carefully turn the bottles full of sodium sulfate solution and put each of them over one of the needles.
5. Wait until the bottle connected with the negative terminal of the battery is full of gas.
6. Ask your teacher to demonstrate a test for pure hydrogen ("negative oxyhydrogen test").
7. In the other bottle a test for pure oxygen is made ("glowing paper test").
Models of smallest particles in air, hydrogen, oxygen, water.       THIS ANALYSIS WITH AN ACID BASE INDICATOR