To create such an alien tentacle snake as shown in the video, ignite a small pile of cigarette ash and 3–5 table spoons of spiritus with 2–3 tablets of sodium bicarbonate (baking powder) and sugar (e.g., Emser pastilles).
The sugar melts when heated. It first becomes brown and finally burns to black, solid carbon (C12H22O11 → 12 C + 11 H2O). At the same time, the sodium bicarbonate decomposes (2 NaHCO3 → Na2CO3 + CO2 + H2O). This releases CO2 that inflates the liquid sugar so that a very light, foamed mass is formed, which pushes itself as a "black snake" or alien out of the flame as more and more of it is formed. The snake mainly consists of carbon from the heated sugar.
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