In the previous experiment you have separated a colourless inflamable liquid from fermented Cola.
Like in methylated spirit this liquid contains alcohol.
* Make a micro spirit burner from a Liquemin bottle using a wick from tissue paper, add spirit, inflame it.
* Left and middle: Hold the aluminium closure of a cola can above the top of the flame:
Observation:  The metal is glowing. A liquid collects but no drop is falling down.
* Right:              The top of the spirit flame has a temperature of 835° C.
Explanation: The molten aluminium is covered by an invisible layer of solid alumionium oxide.