Alternative Hofmann Experiment 2: Brine covered by olive oil
Take  safety precautions concerned with electricity. Work on a tray Left: In this experiment the Hofmann Apparatus is replaced by a H-shaped container. The brine is covered by a layer of olive oil.
Observations after replacing the paper clip anode by a platinum electrode:
* Gas bubbles at both electrodes.
* Middle and right: The layer of  olive oil disappears at the cathode side. More and more foam appears.
* no photo: The olive oil is transformed into a semisolid substance
Explanations:  Red: 2 H₂O(l)  + 2 e- -->  H₂(g) + 2 OH-(aq)
Saponification of the olive oil by the sodium hydroxide formed at the cathode:          Fatty oil + 3 NaOH(aq) ---------> Glycerol + 3 R-COONa(aq)
                                Ox:       Cl^-(aq)  --> Cl₂(g)  + 2 e ^-
 Addition of chlorine by double bonds of fatty oils 

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